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Core–shell spiny globe shaped Co2P@Ni2P/NiCo2O4@CoO–NF (CNNCC–NF) was constructed. The CNNCC–NF shows ultrahigh areal capacitance (10.11 F cm−2 at 2 mA cm−2). The CNNCC–NF//AC–NF device exhibits a high energy density and excellent stability.

Metal–organic frameworks (MOFs) are promising electrode materials for supercapacitors; however, their electrochemical performances are limited by their low electrical conductivities. To address this problem, “conductive ink” poly(3,4-ethylenedioxythiophene) (PEDOT) was used to enhance the conductivity, while “electron sponge” polyoxometalate [PMo12O40]3− (PMo12) with large electronic transfer capability was used as the capacitance contributor. Finally, MOFs (PCN-224) acted as the host of this composite that provided the electrical double-layer capacitor and a PCN-224@PEDOT/PMo12–CC-II hierarchical hollow micro-vesicle nanostructure was obtained via a simple one-step electro-codeposition. The microvesicle nanocomposite was interspersed in MOF hosts. Benefiting from the novel structure and the synergistic effect of three components, the optimal areal capacitance of the PCN-224@PEDOT/PMo12–CC-II electrode was 4077.8 mF cm−2 at 5 mA cm−2 (the concentration ratio of EDOT : PMo12 is 1 : 0.75), which is 32.9 times more than that of pristine PCN-224 (123.6 mF cm−2). Furthermore, a symmetric supercapacitor device was constructed by the PCN-224@PEDOT/PMo12–CC-II nanocomposite, which possessed an excellent energy density of 0.297–0.0192 mW h cm−2 (at a power density of 0.324–5.128 W cm−2) and a good long-term cycle ability (84.59% for 10 000 cycles at 5 mA cm−2). This study presented a one-step electro-deposition synthetic strategy for the design and fabrication of the high-capacitance MOF-based electrode material, which showed great promise in the future design of high-performance materials for advanced energy production.

Polyoxometalates (POMs) can act as an electron reservoir, giving rise to mixed-valence colored state species without their structural changes. This unique feature of POMs has led to the development of POM-based electrochromic devices (ECDs), which show several advantages over organic and inorganic material-based ECDs. For example, the EC properties of POMs can be tuned through molecular design. Furthermore, POMs show high chemical and UV stabilities. In this review, POM structures and the preparation methods for the EC films of POMs were comprehensively introduced. To avoid the dissolution of POM films in electrolyte media or to prepare a homogeneous transparent POM film, a stabilizer was introduced. Several types of stabilizers, including ionic types and carbon materials, were also reviewed for POM films. The EC properties of POMs depend primarily on their structural diversity. Thus, we reviewed the EC properties of different POM films prepared from diverse structures. In addition, we described the EC properties of the POM films that were obtained via different preparation methods and exhibited different morphologies. Furthermore, several types of POM-based ECDs were introduced so that not only electrochromic functions but also capacitive functions could be integrated in the ECD. This review may be of interest to researchers in the ECD field devoted to improving the material stability, optical contrast, and design of new POM structures as well as those engaged in the extension of POMs to functional materials.

A bifunctional catalyst, Pd nanoparticles (NPs) encapsulated in MIL-101, has been synthesized by capillary impregnation. The as-prepared Pd@MIL-101 was characterized by powder X-ray diffraction, N2 physisorption, X-ray photoelectron spectroscopy, transmission electron microscopy, and high-angle annular dark field scanning transmission electron microscopy, indicating that Pd NPs were highly dispersed in the pores of MIL-101 without deposition of the nanoparticles on the external surface or aggregation. The bifunctional catalyst of Pd@MIL-101 exhibited highly catalytic activity for alcohol oxidation and aldimine condensation one-pot reactions, where Pd NPs affords good oxidation activity and MIL-101 offers Lewis acidity. In particular, Pd@MIL-101 yielded an effective catalytic performance with toluene as the solvent, K2CO3 as the co-catalyst, and 353 K as the optimum reaction temperature for the one-pot reaction. After five cycles of reuse, Pd@MIL-101 still shows high catalytic performance. Above all, it is found that the enhanced catalytic performance was achieved via the synergistic cooperation of MIL-101 and Pd NPs.

In order to accurately calibrate the static error model coefficients of three gyroscopes simultaneously, especially the higher-order coefficients, in an inertial measurement unit, an optimal 16-position method is designed. Analysis is conducted using a precision centrifuge with a counter-rotating platform, and coordinate systems are established on centrifuge. Thus, centrifuge error sources, which may affect the calibration accuracy of a gyroscope’s drift coefficients, are analyzed, corresponding to the coordinate systems established. Precise expressions for the input angular rate and the input specific forces on each axis of the three gyroscopes are derived using a homogeneous transformation method. The influence of centrifuge error on the drift coefficients is analyzed, and the calibration accuracy can be improved by compensating for the influence of centrifuge error. The 16-position calibration method is validated through simulation, which establishes that centrifuge errors such as Δθy2t, Δθy2(−Ωt), Δθx2t, Δθx2(−Ωt), and ΔΩ mainly influences the bias MF and first-order drift coefficients MI and MS, but has little impact on higher-order coefficients. The calibration process is simple and short time-consuming, and the calibration accuracy is satisfied to requirement. After compensating for the main centrifuge errors, the 16-position method will further increase the accuracy of an inertial navigation system.

In recent years, large numbers of hydrophobic/superhydrophobic metal-organic frameworks (MOFs) have been developed. These hydrophobic MOFs not only retain rich structural variety, highly crystalline frameworks, and uniform micropores, but they also have lower affinity towards water and boosted hydrolytic stability. Until now, there were two main strategies to prepare hydrophobic MOFs, including a one-step method and post-synthesis modification (PSM). PSM was an often-used strategy for preparing hydrophobic MOFs. Hydrophobic MOFs showed unique advantages when used as catalysts for various categories of reactions. Herein, recent research advances relating to hydrophobic MOFs in the catalytic field are presented. The catalytic activities of hydrophobic MOFs and corresponding hydrophilic ones are also compared, and the superiority of hydrophobic MOFs or MOF materials as catalysts in 10 reactions is discussed. Finally, the advantages of hydrophobic MOFs as catalysts or auxiliary materials are summarized and promising future developments of hydrophobic MOFs are highlighted.

Fall armyworm, Spodoptera frugiperda (Smith), has caused significant losses for crop production in China. The fall armyworm is mainly controlled by the chemical insecticides, whereas the frequent application of insecticides would result in the resistance development. Insect cytochrome P450 monooxygenases play an essential part in the detoxification of insecticides. In this study, five P450 genes were selected to determine the role in response to insecticides by RNA interference (RNAi). Developmental expression pattern analysis revealed that S. frugiperda CYP321A8, CYP321A9, and CYP321B1 were highest in second-instar larvae among developmental stages, with 2.04-, 3.39-, and 8.58-fold compared with eggs, whereas CYP337B5 and CYP6AE44 were highest in adult stage, with 16.3- and 10.6-fold in comparison of eggs, respectively. Tissue-specific expression pattern analysis exhibited that CYP321A8, CYP321B1, and CYP6AE44 were highest in the midguts, with 3.56-, 3.33-, and 3.04-fold compared with heads, whereas CYP321A9 and CYP337B5 were highest in wings, with 3.07- and 3.36-fold compared with heads, respectively. RNAi was also conducted to explore detoxification effects of the five P450 genes on chlorantraniliprole. The second-instar larvae became more sensitive to chlorantraniliprole with a higher mortality rate than the control, after silencing CYP321A8, CYP321A9, and CYP321B1, respectively. These findings strongly supported our viewpoint that CYP321A8, CYP321A9, and CYP321B1 may play a critical role in insecticide detoxification. It will provide a basis for further study on regulation of P450 genes and the management of S. frugiperda.

In this work, porous decatungstate-TiO 2 composite thin film has been prepared by the electrodeposition method. The advantages of decatungstate as electrochromic material are discussed and the electrochromic performances of the composite film have also been systematically investigated. The transmittance decreased from 98.0% down to 50.8% at the wavelength of 550 nm under an applied potential of − 0.8 V. Good reversibility and reproducibility also can be observed in the composite electrochromic film. The porous structure of the composite film not only provides a large surface area for loading W 10 polyanions but is also beneficial for the fast diffusion of H + , which results in high electrochromic performances.

In order to accurately calibrate the gyroscope's drift coefficients, the coordinate systems are established on precision centrifuge with counter-rotating platform, and the corresponding error sources of each coordinate system are analyzed. The precise input angular rate along each axis of gyroscope are derived by homogeneous transformation method and also the nominal input specific forces are given. The precise expression of each drift coefficient is provided combining with gyroscope's error model, input specific forces and angular rates of gyroscope at the 16-position. And the compensation for the identification results can be conducted by the expression. It can be shown that through simulation two coefficients are significantly influenced by centrifuge errors when using the 16-position calibration method, and centrifuge errors have no impacts on other coefficients, which proves that the method can effectively eliminate the impacts of centrifuge errors. Only several centrifuge errors should be considered in actual calibration such as the perpendicularity between the counter rotating platform's revolving axis and the working base, the wobbles of counter rotating platform, and the difference between the angular rate of counter rotating platform and the one of the main axis.

MOF-templated nitrogen-doped porous carbon materials (NPCs) have been prepared by employing the previously reported MOF, [(CH3)2NH2]6[Ni(H2O)6]3{Ni6(η6-TATAT)4(H2O)12}, as a precursor, which can act as efficient electrocatalysts for oxygen reduction reactions (ORRs). The carbonized MOF acts as the carbon source, and urea is employed as an additional nitrogen source. The urea modified carbon materials, carbonized at 800 °C, 900 °C and 1000 °C under Ar atmosphere, all show electrocatalytic activity for ORRs; the material carbonized at 900 °C exhibits a more appropriate nitrogen content, robust pore structure and an excellent degree of graphitization. In alkaline media, NPC-900 exhibits superior catalytic activity (the onset and half-wave potentials are −0.06 V and −0.23 V vs. Ag/AgCl, respectively), excellent long-term durability and outstanding methanol tolerance compared with the commercial Pt/C catalyst.

The mechanism of the excited-state double proton transfer (ESDPT) reactions of 8-hydroxyquinoline (8HQ) along three types of hydrogen-bonded bridges—ammonia (NH3), water (H2O) and acetic acid (AcOH) has been investigated by using time-dependent density functional theory. Based on the analysis of hydrogen bond strengths and the excited-state potential energy surfaces (PES) along the proton transfer coordinates, it is concluded that the hydrogen bonds play the key role in the excited-state multiple proton transfer reaction. Moreover, three different concerted mechanisms have been found in 8HQ·NH3, 8HQ·H2O and 8HQ·AcOH complexes. Upon photoexcitation, the deprotonation of a hydroxyl group in 8HQ would occur first in 8HQ·NH3 due to the stronger hydrogen bond –OH⋯NH3. On the contrary, the hydrogen bond –OH⋯O–C–OH is much weaker in the 8HQ·AcOH complex, and this leads to a fast protonation of –N– in the 8HQ moiety. For the 8HQ·H2O complex, the hydrogen bond strengths are almost the same, so that both protons would transfer simultaneously in a symmetrical and concerted fashion.

A microporous hexanuclear europium cluster based MOF, (DMA)2[Eu6(μ3-OH)8(BPDC)6(H2O)6]n·(solv)x (DMA = dimethylamine cation and H2BPDC = [1,1′-biphenyl]-4,4′-dicarboxylic acid), can be applied as a highly selective and sensitive bifunctional luminescence sensor to detect nitrobenzene and 4-aminophenol through an energy competition mechanism. More interestingly, this MOF can detect nitrobenzene and 4-aminophenol with low detection limits of 5–70 ppm and 5–110 ppm, respectively.

In this study, a series of FeSAPO-44 molecular sieves are synthesized by a facile like-dry-gel method. The untreated bauxite is used as the source of Al, Si, while Fe element is retained as the acid site. Rice husks are provided for auxiliary Si source together with Si-sol to balance Al/Si ratio, and its cellulose plays a role in favoring Fe of bauxite into the framework of molecular sieves. The referred sample derived from pseudo-boehmite confirms rice husk facilitates Fe enter the skeleton. The referred sample synthesized from ethyl cellulose further affirmed the function of cellulose. The crystal structure, surface area, pore diameter, surface properties and acidity of samples are systematically characterized. Furthermore, the obtained FeSAPO-44 molecular sieve from natural source of bauxite and rice husk is used as a carrier to support Mo for the hydrocracking of Karamay super heavy oil, which shows a feasible practical application.

An In-based metal-organic framework, with 1D nanotubular open channels, In2(OH)(btc)(Hbtc)0.4(L)0.6·3H2O (1), has been synthesized via an in situ ligand reaction, in which 1,2,4-H3btc is partially transformed into the L ligand. Compound 1 exhibits exceptional thermal and chemical stability, especially in water or acidic media. The activated 1 presents highly selective sorption of carbon dioxide (CO2) over dinitrogen. Interestingly, diffuse-reflectance infrared Fourier transform spectroscopy with a carbon monoxide probe molecule demonstrates that both Lewis and Brønsted acid sites are involved in compound 1. As a result, as a heterogeneous Lewis and Brønsted acid bifunctional catalyst, 1 possesses excellent activity and recyclability for chemical fixation of CO2 coupling with epoxides into cyclic carbonates under mild conditions. In addition, the mechanism for the CO2 cycloaddition reaction has also been discussed.

In this research, three vanadium substituted polyoxometalates (POMs) K3+n[PW12−nVnO40] (abb. PW12−nVn) (n = 1, 2, 3)-based electrochromic (EC) films were prepared using the electrodeposition method. The films not only show a good performance in terms of EC properties in an H+-based aqueous electrolyte, but also show good EC performance in a Li+-based non-aqueous electrolyte. Although the EC activity of POMs is lower in the neutral media than in acid media, the use of the neutral non-aqueous electrolyte does not result in the suppression of the EC performance. The large diffusion coefficient of the Li+ in the porous films guarantees the high performance. For the PW11V, PW10V2 and PW9V3-based films, the coefficients of Li+ are 4.05 × 10−11, 4.11 × 10−11, and 1.04 × 10−11 cm2 s−1, respectively. The PW10V2-based film shows the shortest response time for coloration which is even shorter than that shown in the H+-based aqueous electrolyte. The optical contrast of the films is also nearly the same as which achieved in the aqueous electrolyte media. The application of the non-aqueous neutral electrolyte would be beneficial for the fabrication of the POM-based EC device.

In this paper, we develop a facile and convenient two-step strategy for preparation of ZIF-8/ZnO/K6P2W18O62 (P2W18) ternary composite materials for the first time. ZIF-8/ZnO are fabricated by a “direct mixing” synthesis strategy and served as the substrate for subsequent P2W18 deposition. Then, ZIF-8/ZnO/P2W18 ternary composite was prepared in P2W18 aqueous solution through electrostatic interaction process. Further, the composites with different loading of P2W18 were achieved by reacting with different concentration of P2W18 aqueous solution. The as-prepared composite materials were characterized and confirmed by powder X-ray diffraction, TEM, EDS, ICP, FT-IR spectra, UV–Vis diffuse reflectance spectroscopy, and electrochemical test. It is noteworthy that the hybrid composites exhibit high efficient activities in the removal of cationic dyes, which could be ascribed to the high adsorption capacity derived from the strong electrostatic interaction between P2W18 and cationic dyes. Based on the investigation, the composites have potential application for waste water purification.

exploiting marine energy is an important measure to promote "marine economy" development and maintain national security, and based on which, designed and introduced a new horizontal axis turbine marine energy generation system which mainly included energy capturing system, energy transfer system, security service system and remote monitoring system. It proved the feasibility and the high efficiency of the system from the tank experiment, which provides a reliable design idea and reference for the similar engineering project.

An InIII-based anionic framework (InIII-MOF) with 4-connected SrAl2 topology was constructed. The InIII-MOF with permanent porosity functions as a host for encapsulation of Ln3+ ions through ion-exchange processes. The photophysical properties of the as-prepared Ln3+@InIII-MOF were investigated and the results showed that the InIII-MOF could serve as an antenna to sensitize Ln3+ cations, especially suitable for Tb3+ and Eu3+ ions. The possible sensitization mechanism has been studied by surface photovoltage spectroscopy. Additionally, the InIII-MOF could also act as a host material when applied in the separation and purification of cationic dyes, which is highly based on the size and charge of organic dyes. Moreover, it can be used as a chromatographic column stationary phase to separate cationic dyes more efficiently and selectively. It is believed that the as-prepared InIII-MOF may have potential applications in optical materials and environmental fields.

Now the world is running short of source and the human beings are developing different kinds of new energy resources. This article introduced and analysis several kinds of wave power devices, tells the advantage and disadvantages. There is a great improvement in the modern wave power generating sets, but still some technology bottlenecks, we should work on these challenges and make full use of the ocean energy resources with the lowest cost.

With the development of economy, the global satellite navigation system with its high speed, high efficiency, high precision measurement and positioning a series of significant advantages, favored by various industry data collection and monitoring of personnel resources , the advent of satellite navigation systems to solve a large-scale, rapid and high-precision global positioning problem. Its scope of application has penetrated to the various departments of the national economic and social development in various fields and industries. To be able to monitor the progressive realization of automated data collection and transmission, the urgent need to adopt advanced positioning technology to build real-time location monitoring system PC Based Development Background navigation receiver , an overview of the inter Beidou BD-126 systems and microcontrollers can be serially the basic principle of mouth communication describes the communication protocol Compass BD-126 positioning module and the next crew between the microcontroller to control development in the use of PC positioning system for a detailed description , including the BDS Beidou satellite navigation module and microcontroller serial data communications, microprocessor controlled real-time data display , and so on

In recent years, the concept of renewable energy has been deepening and popularization, all kinds of new energy technology is developed by leaps and bounds, a growing number of wave energy devices has been put into use and has a very good prospect. In wave power generation equipment, the conversion transmission device is a very important unit, which involving energy transfer, adjustment, stable output and buffer storage, so it need to be well designed to satisfy the operational requirement by taking advantage of different parts. By analyzing the commonly used conversion transmission devices, the characteristics of transmission devices and wave power generation equipments, we proposing a design of a flexible transmission device which can change its torque capacity with clutch automatic control device, in the form of its layout to drive a train of thought for the design wave energy conversion.