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Poly(aryl piperidinium) (PAP) anion exchange membranes (AEMs) furnish an important avenue for the commercialization of anion exchange membrane fuel cells (AEMFCs), but their ionic conductivity and alkali resistance still need to be improved. Here, we report the synthesis of PAP AEMs with a branched structure by the acid-catalyzed reaction and compare them with the main-chain AEMs. The experimental results show that the branched AEMs have higher OH

Wireless sensor networks (WSNs), one of the fundamental technologies of the Internet of Things (IoT), can provide sensing and communication services efficiently for IoT-based applications, especially energy-limited applications. Clustering routing protocol plays an important role in reducing energy consumption and prolonging network lifetime. The cluster formation and cluster head selection are the key to improving the performance of the clustering routing protocol. An energy-efficient routing protocol based on multi-threshold segmentation (EERPMS) was proposed in this paper to improve the rationality of cluster formation and cluster head selection. In the stage of cluster formation, inspired by multi-threshold image segmentation, an innovative node clustering algorithm was developed. In the stage of cluster head selection, aiming at minimizing the network energy consumption, a calculation theory of the optimal number and location of cluster heads was established. Furthermore, a novel cluster head selection algorithm was constructed based on the residual energy and optimal location of cluster heads. Simulation results show that EERPMS can improve the distribution uniformity of cluster heads, prolong the network lifetime and save up to 64.50%, 58.60%, and 56.15% network energy as compared to RLEACH, CRPFCM, and FIGWO protocols respectively., 16 pages, 24 figure, 4 tables

Finesse is a critical parameter for describing the characteristics of an optical enhancement cavity (OEC). The paper first presents a review of finesse measurement techniques, including a comparative analysis of the advantages, disadvantages, and potential limitations of several main methods from both theoretical and practical perspectives. A variant of the existing method called the free spectral range (FSR) modulation method is proposed and compared with three other finesse measurement methods: the fast-switching cavity ring-down (CRD) method, the rapidly swept-frequency (SF) CRD method, and the ringing effect method. A high-power OEC platform with a high finesse of approximately 16,000 is built and measured with the four methods. The performance of these methods is compared, and the results show that the FSR modulation method and the fast-switching CRD method are more suitable and accurate than the other two methods for high-finesse OEC measurements. The CRD method and the ringing effect method can be implemented in open loop using simple equipment and are easy to perform. Additionally, recommendations for selecting finesse measurement methods under different conditions are proposed, which benefit the development of OEC and its applications.

Dengue remains a public health issue worldwide. Similar to chronic infectious diseases, stimulation of cytokine production is not enough to drive immune effector cells for effective virus clearance. One possible mechanism is the virus induces a large number of negative stimulatory cytokines inhibiting immune response. Interleukin 37 (IL-37) plays a crucial regulatory role in infection and immunity, inhibits innate and adaptive immunity as an anti-inflammatory cytokine by inhibiting proinflammatory mediators and pathways. To date, there are few studies reporting correlations between dengue fever (DF) and IL-37. In this study we found that the serum IL-37b and IL-37b-producing monocytes in patients were significantly increased in DF patients. A majority of the IL-37b produced by DF patients was produced by monocytes, not lymphocytes. Increased levels of IL-6, IL-10, and IFN-α were also found in DF patients. However, we failed to detect IL-1β, IL-17A and TNF-α in plasma, because of off-target. In our study, there was no relation between IL-6, IL-10, and IFN-α expressions and IL-37b in serum (P > 0.05). The IL-37b-producing monocytes were negatively correlated with the level of IFN-α in serum and platelet count, and positively correlated with lymphocytes percentage (P P

Adsorbed SO2 on Pt sites can be substituted by NO; adsorbed NO can be completely reduced to NH4+ and removed in a reduction potential range.

Simultaneously achieving high electrochemical activity and high loading for solid-state batteries has been hindered by slow ion transport within solid electrodes, in particular with an increase in electrode thickness. Ion transport governed by ‘point-to-point’ diffusion inside a solid-state electrode is challenging, but still remains elusive. Herein, synchronized electrochemical analysis using X-ray tomography and ptychography reveals new insights into the nature of slow ion transport in solid-state electrodes. Thickness-dependent delithiation kinetics are spatially probed to identify that low-delithiation kinetics originate from the high tortuous and slow longitudinal transport pathways. By fabricating a tortuosity-gradient electrode to create an effective ion-percolation network, the tortuosity-gradient electrode architecture promotes fast charge transport, migrates the heterogeneous solid-state reaction, enhances electrochemical activity and extends cycle life in thick solid-state electrodes. These findings establish effective transport pathways as key design principles for realizing the promise of solid-state high-loading cathodes.

A versatile microporous metal-organic framework (MOF), {[Cu(TIA)]·1.5CH3OH}n (Cu-1), was successfully obtained via the solvothermal reaction of cuprous(II) salt with the bifunctional ligand 3-(1H-1,2,4-triazol-1-yl)isophthalic acid. Single-crystal X-ray diffraction studies indicate that Cu-1 contains an apo three-dimensional skeleton and two types of one-dimensional channels. The framework of Cu-1 has excellent acid-alkali resistance and thermal stability, which is stable in a pH = 2-13 aqueous solution and an 260 °C air environment. In addition, the microporous copper MOF shows very high uptakes of CO2 (180 cm3·g-1) and C2H2 (113 cm3·g-1) at 273 K and displays excellent adsorption selectivity for small molecular gases. The ideal adsorbed solution theory selectivity values for C2H2/C2H4, CO2/CH4, and CO2/N2 are 2, 9, and 22 at 298 K, respectively. At the same time, breakthrough experiments for CO2/CH4, CO2/N2, and C2H2/C2H4 were further conducted to verify the efficient separation performances.

The exploration of innovative molecular switches has resulted in large developments in the field of molecular electronics. Focusing on a single molecular switch with different forms exhibiting different electride features, potassium-atom-doped all-cis 1,2,3,4,5,6-hexafluorocyclohexane K-F6C6H6 was studied theoretically. It was found that an oriented external electric field can drive excess electron transfer from the region outside of the K atom to that outside of F6C6H6. Subsequently, the electride-like molecule K-F6C6H6 (1) switches into the molecular electride K-F6C6H6⋯e− (3) through another electride-like molecule K-F6C6H6 (2). The static first hyperpolarizabilities (β0) are increased over 12- and 5-fold when moving from 1 to 2 and 3, respectively. The rise of each β0 value constitutes an order of magnitude improvement. Between them, the different β0 values suggest that K-F6C6H6 is a good candidate for use as a multiple-response nonlinear optics switch. The order of the β0 values of 1–4 for M-F6C6H6 (M = Li and Na) coincide with that of K-F6C6H6, also exhibiting a switch effect.

Indole-3-acetic acid (IAA) plays an important role in the growth and development of plants. In this study, a series of predominant strains were isolated and identified as Enterobacter sp. with remarkable IAA-producing capabilities. The IAA-producing strains are mainly tryptophan-dependent and have significantly high yields of IAA (3477 μg mL−1 and 3378 μg mL−1). The ipdC gene encoding indole-3-pyruvate decarboxylase was identified by genomic analysis and RT-qPCR analysis, indicating the involvement of the indole-3-pyruvic acid (IPyA) pathway of IAA biosynthesis. The IPyA pathway was also confirmed by the intermediate assay. The IAA product of microbial metabolites was isolated, purified and characterized. These microbes exhibiting IAA production significantly promoted the growth of maize, increasing root length, plant height, fresh weight and dry weight. Thus, Enterobacter sp. with high IAA production has great prospects in agricultural and industrial applications.

Exploration of novel molecular switches is an ongoing hot issue in molecular electronics. Alkalides and electrides are two typical representatives of excess electron compounds. It was found that M(HF)3M (M = Li or Na) induced by an oriented external electric field are good candidates for inorganic multi-response nonlinear optical (NLO) molecular switches. Their off forms (C3h) exhibit electride-like super alkali earth atom characteristics, while their on forms (C3v) exhibit charming superalkalide (M = Na or Li) or superalkali electride characteristics (M = Li). The increases of the static first hyperpolarizabilities (βe0) from off to on forms constitute a 2–3 orders of magnitude improvement for both M = Li and Na. These extremely large differences in βe0 reinforce the potential of M(HF)3M for applications in excellent multi-response nonlinear optical materials.

A series of platinum(II) complexes with controllable color emission obtained by regulating intra/intermolecular interactions have been synthesized. These complexes are highly emissive both in solution and in the solid state with microsecond lifetimes, attributed to the single molecular (3IL), excimer, and aggregation emission from their different excited states. All complexes display interesting color changeable photoluminescence depending on concentrations, excitation wavelengths, and good/poor solvents, and exhibit reversible vapochromic/mechanochromic behaviors, which are applicable in emission readable barcode modules and color changeable logo design. Furthermore, using the complexes as emitting materials coated on commercial NUV-LED chips, bright yellow to orange luminescence with a maximum output of 8434 cd m−2 and external quantum efficiency (EQE) of 2.58% could be achieved, providing a facile method to apply platinum(II) complexes in the solid state lighting field.

Based on the brain-gut axis, the present study investigated the effect of Huanglian Houpo Decoction(HLHPD) in the treatment of ulcerative colitis(UC) and explored the mechanism in the regulation of 5-hydroxytryptamine(5-HT), substance P(SP), and vasoactive intestinal peptide(VIP) using modern technologies and molecular docking. Sixty male C57 BL/6 J mice were randomly divided into a blank control group, a model group, a sulfasalazine(SASP) group, and high-(5.00 g·kg~(-1)), medium-(2.50 g·kg~(-1)), and low-dose(1.25 g·kg~(-1)) HLHPD groups. The UC model was induced by oral administration of water containing 3% dextran sulfate sodium salt(DSS) in mice except those in the blank control group. After HLHPD was administered for 10 days, the mice were sacrificed for sample collection. Morphological changes of colon tissues were observed by HE staining. The expression of 5-HT, SP, VIP, tumor necrosis factor α(TNF-α), interleukin-6(IL-6), and interleukin-1β(IL-1β) in the hypothalamus, serum, and colon was determined by the enzyme-linked immunosorbent assay(ELISA). The expression of tryptophan hydroxylase 1(TPH1), SP, and VIP in colon tissues was evaluated by immunohistochemistry. The expression of brain-gut peptide receptors, such as 5-HT3 A, neurokinin receptor 1(NK-1 R), and VIP receptor 1(VPAC1) in colon tissues was investigated by Western blot. The binding affinity of the brain-gut peptide receptors to the main components of HLHPD was analyzed by molecular docking. After HLHPD intervention, UC mice showed increased body weight, reduced DAI score and occult blood, prolonged colon, down-regulated levels of TNF-α, IL-1β, and IL-6 in colon tissues, and relieved pathological damage in the colon. The VIP levels in the colon were significantly up-regulated in the HLHPD groups. The high-and medium-dose HLHPD could significantly down-regulated SP and 5-HT in colon tissues and 5-HT in the serum, and up-regulated the VIP in the serum. The high-dose HLHPD group could down-regulate 5-HT and up-regulate VIP in the hypothalamus. It is suggested that HLHPD can reverse the levels of brain-gut peptides in UC mice to varying degrees. Correlation analysis results suggested that the expression levels of brain-gut peptides in the hypothalamus, serum, and colon tissues were related to inflammatory factors. Molecular docking results showed that berberine, coptisine, and epiberberine were presumedly the material basis for HLHPD in regulating the levels of 5-HT3 A, NK-1 R, and VPAC1. The main components of HLHPD may reduce colonic inflammation and pathological damage of colon tissues by regulating the activity of brain-gut peptides and their receptors, thereby reducing DSS-induced colitis in mice.

As the extension of the linear inverted pendulum &#x0028 LIP &#x0029 and planar inverted pendulum &#x0028 PIP &#x0029 , this paper proposes a novel spatial inverted pendulum &#x0028 SIP &#x0029 . The SIP is the most general inverted pendulum &#x0028 IP &#x0029 than any existing IP. The model of the SIP is presented for the first time. The SIP inherits all the characteristics of the LIP and the PIP, which is a nonlinear, unstable and underactuated system. The SIP has five degrees of motion freedom and three control forces. Thus, it is a multiple-input and multiple-output &#x0028 MIMO &#x0029 system with nonlinear dynamics. To realize the spatial trajectory tracking of the SIP, the control structure with five PID controllers will be designed. The parameter tuning of the multiple PIDs is a challenging work for the proposed SIP model. To alleviate the difficulties of the parameter tuning for the multiple PID controllers, optimal PIDs can be achieved with the help of Big Bang-Big Crunch &#x0028 BBBC &#x0029 optimization. The BBBC algorithm can successfully optimize the parameters of the multiple PID controllers with high convergence speed. The optimization performance index of the BBBC algorithm is compared with that of the particle swarm optimization &#x0028 PSO &#x0029 . Simulation results certify the rightness and effectiveness of the proposed control and optimization methods.

Let x = (x’,x”) with x’∈ ℝk and x” ∈ ℝN-k and Ω be a x’-symmetric and bounded domain in ℝN (N ≥ 2). We show that if 0 ≤a ≤ k−2, then there exists a positive constant C > 0 such that for all x’-symmetric function u ∈ C∞0 (Ω) with ∫Ω∇u(x)N−ax’−adx ≤ 1, the following uniform inequality holds $$\frac{1}{{{{\int_\Omega {|x|} }^{ - a}}dx}}\int_\Omega {{e^{\beta a|u|\tfrac{{N - a}}{{N - a - 1}}}}} |x'{|^{ - a}}dx \leqslant C,$$ where $${\beta _a} = N(N - a)(\frac{{2\pi \tfrac{N}{2}\Gamma (\tfrac{{k - a}}{2})}}{{\Gamma (\tfrac{k}{2})\Gamma (\tfrac{{N - a}}{2})}})\tfrac{1}{{N - a - 1}}$$. Furthermore, βa can not be replaced by any greater number. As the application, we obtain some weighted Trudinger–Moser inequalities for x-symmetric function on Grushin space.

Elucidations on the structure-activity correlations of non-Pt coordination polymer (CP)-based photocatalysts are highly significant for both the enhancement in catalytic activity and large-scale industrial applications of sustainable hydrogen from water splitting. Herein, three isostructural [Cu(HL)2(R-BDC)]n (denoted as Cu-CP-R, HL = 4'-(4-hydroxyphenyl)-4,2':6',4''-terpyridine, R-BDC = 2-R-1,4-benzenedicarboxylate, R = NO2, OH and Br) CPs were solvothermally synthesized by varying the substituents attached to benzenedicarboxylate, which together with two previously reported analogues (R = NH2 and H) were used as photocatalysts to systematically explore the substitution effect on the hydrogen evolution activity. These five CPs feature isomorphic layered motifs with axially elongated CuII octahedra extended alternately by ditopic HL and R-BDC2- connectors, in which R behaves structurally as a non-coordinate group. The hydrogen production rate over the Cu-CP-R photocatalysts increased from 0.21 to 2.34 mmol g-1 h-1, which followed the order of -NH2 > -NO2 > -H > -OH > -Br. Furthermore, the combined experimental and theoretical investigations reveal that the free R moiety significantly dominates the photocatalytic activity by shifting the d states of the CuII ion towards the Fermi level, controlling the potential of the conduction band and quickening the charge transfer ability. These important findings can provide informative hints for the design of high-performance, earth-abundant non-noble metal CP-based semi-conductive photocatalysts.

The orientation of hydrocarbon chains plays a key role in the applications of organic materials. And chain folding in the process of molecular orientation is also of great significance for the design of organic molecular thin films. The effect of chain length and simulation temperature on the isothermal orientation of n-alkanes on graphene surface is studied by molecular dynamics simulation in this paper. And the chain folding is also described. The n-alkanes can form perpendicular ordered structure, parallel ordered structure or perpendicular orientation at relative low temperature and parallel orientation at relative high temperature on graphene surface. The chain fold happens when long n-alkanes form perpendicular ordered structure on graphene surface. And the simulation results show the interactions of n-alkane−graphene and n-alkane−n-alkane affect chain fold.