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Dehydrochlorination of 1,3‐dichloropropanol with alkali is a key step to industrially produce epichlorohydrin. But there are many side reactions involved in the synthesis process. In this work, a complete mechanism and kinetics investigation of the related reaction network was constructed. Density functional theory simulation method was first used to simulate the possible reactions so as to confirm the reaction mechanism and simplify the reaction network. Based on the simulation results, the complex reaction network was simplified into a three‐step consecutive reaction. The kinetic parameters of the three consecutive steps, including the order of the reaction, the pre‐exponential factor, and activation energy, were experimentally determined by conductance and other methods. All the experimental results are basically consistent with the simulation. The obtained kinetics data provide a basis for epichlorohydrin synthesis process optimization. [ABSTRACT FROM AUTHOR]

Liquid-liquid mixing, including homogeneous and heterogeneous mixing, widely exists in the chemical industry. How to quantitatively characterize the mixing performance is important for reactor assessment and development. As a convenient and direct method for mixing characterization, the chemical probe method uses some special test reactions to characterize the mixing results. Here, the working principle and selection requirements of this method are introduced, and some common chemical probe systems for homogeneous and heterogeneous mixing processes are reviewed. The characteristics and applications of these systems are illustrated. Finally, the development of the new system is proposed. [ABSTRACT FROM AUTHOR]

Mixing of two immiscible liquids consists of two sections that are liquid‐liquid dispersion and mass transfer intraphase or interphase. It plays a crucial role in the liquid‐liquid heterogeneous reactions. Here, the liquid‐liquid heterogeneous mixing efficiency in RPB reactor is experimentally assessed by a consecutive‐competitive chemical probe system. The diameters of dispersed phase droplets in RPB were measured and a correlation to predict the mean diameters were obtained. Based on the dispersed phase size and mass transfer characteristic, a model for predicting the segregation index of liquid‐liquid heterogeneous mixing in RPB was established with a deviation <20%. Based on this model, the characteristic time of liquid‐liquid heterogeneous mixing in RPB is determined to be in the range of 0.01–1 s. RPB exhibits a great process intensification potential for heterogeneous mixing process. [ABSTRACT FROM AUTHOR]

Herein, the formation mechanism of Ni‐Al layered double hydroxide (NiAl‐LDH) synthesized by coprecipitation was explored. Moreover, NiAl‐LDH was prepared in a rotating packed bed (RPB) under different rotation speeds, which shows that increasing the rotation speed decreases the lateral size and thickness of NiAl‐LDH, since high rotation speed accelerates the nucleation of NiAl‐LDH. Additionally, the Ni/mixed metal oxides (MMO) catalysts derived from NiAl‐LDH were prepared for maleic anhydride (MA) hydrogenation. Result shows that Ni/MMO catalyst obtained from NiAl‐LDH prepared under a higher rotation speed exhibits higher MA conversion due to its larger surface area and smaller nickel particle size. The Ni/MMO catalyst obtained from NiAl‐LDH prepared under 500 rpm exhibits 100% MA conversion and 100% succinic anhydride selectivity under 30°C and 2 MPa within 1 h. This work provides fundamental insight to understand the formation of NiAl‐LDH. Moreover, RPB as an effective technique to synthesize NiAl‐LDH and Ni‐based catalysts was validated. [ABSTRACT FROM AUTHOR]

Inhibition of Shaker K+ channel activity by external Na+ was previously reported in the melon (Cucumis melo L.) inwardly rectifying K+ channel MIRK and was hypothesized to contribute to salt tolerance. In this study, two inward Shaker K+ channels, CsKAT2 from cucumber (Cucumis sativus) and ClKAT2 from watermelon (Citrullus lanatus), were identified and characterized in Xenopus oocytes. Both channels were inwardly rectifying K+ channels with higher permeability to potassium than other monovalent cations and more active when external pH was acidic. Similarly to MIRK, their activity displayed an inhibition by external Na+, thus suggesting a common feature in Cucurbitaceae (Cucumis spp. Citrullus spp.). CsKAT2 and ClKAT2 are highly expressed in guard cells. After 24 h of plant treatment with 100 mM NaCl, the three KAT2 -like genes were significantly downregulated in leaves and guard cells. Reciprocal chimeras were obtained between MIRK and Na+-insensitive AtKAT2 cDNAs. The chimera where the MIRK S5-P-S6 segment was replaced by that from AtKAT2 no longer showed Na+ sensitivity, while the inverse chimera gained Na+ sensitivity. These results provide evidence that the molecular basis of the channel blockage by Na+ is located in the S5-P-S6 region. Comparison of the electrostatic property in the S5-P-S6 region in AtKAT2 and MIRK revealed four key amino acid residues potentially governing Na+ sensitivity. [ABSTRACT FROM AUTHOR]

The research on the rheological mechanical behaviour of swelling rock in the condition of humidity field has a significant meaning for large rock engineering, such as deep coal mining, tunnelling, and slope engineering. Based on the Nishihara model, considering on the effect of humidity factor on swelling rock, the rheological elements are established and the effects of humidity on the damage of rock, the viscosity, and the elasticity are introduced. Moreover, the viscoelastic plasticity constitutive equations are established under the coupling of swelling rock stress and humidity. Afterward, considering the effects of humidity on the damage, elasticity, and viscosity, the creeping, unloading, and relaxation equations have been deduced. From this research, under the state of low stress σ 3 P < σ S , the Nishihara model which considers the effect of humidity shows the properties of stable creeping. In addition, the unloading curves contain instantaneous elasticity, elastic after effect, and the viscosity flow induced by the humidity. However, under the state of high stress σ 3 P ≥ σ S , it is an unstable creeping model. The unloading curves include instantaneous elasticity, elastic after effect, and the viscosity flow induced by the stress and the humidity. This model reflects the rheological properties of swelling rock comprehensively, and it can be used for rock rheological analysis. [ABSTRACT FROM AUTHOR]

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The reaction of Cu(AC)2·H2O with 4-diethylamino-2-hydrogen-benzaldehyde (Hdahb) in methanol and water under solvothermal conditions leads to the formation of a novel dinuclear complex [Cu2(dahb)4] (1) (C44H56Cu2N4O8,Mr = 896.03,Dcalcd= 1.404 g cm−3). The compound belongs to the monoclinic system space groupP21/c, and was characterized by elemental analysis, IR spectroscopy, and X-ray single-crystal diffraction. It consists of dinuclear unit, which is bridged byμ2-phenolato oxygen. The {Cu2IIO2} core displays dominant antiferromagnetic interactions from the nature of the binding modes throughμ2-O. [Supplemental materials are available for this article. Go to the publisher's online edition of Molecular Crystals and Liquid Crystals to view the free supplemental file.] [ABSTRACT FROM AUTHOR]

At the same condition, utilizing the different of base, the authors constructed two wholly different compounds, 1 and 2. Compounds 1 and 2 are one-dimensional (1D) chainlike, while the coordination mode of dicyandiamide is different in both complexes. In 1, the dicyandiamide isμ1,5-dca bridged coordination mode; in 2, that isμ1,3-dca bridged coordination mode. Two new heterobinuclearnickeland sodium polymers[NiN a(L)(dca)]n(1) and [NiNa(L)(dca)]2n·(CH3COOCH3)n·(H2O)n, (2) [where H2L = N,N′-bis(3-ethoxy- salicylidene)ethylenediamine, dca = N(CN)2–], were synthesized and characterized by elemental analysis and X-ray crystal diffraction. The heterobinuclear complex 1, C22H22N5NaNiO4, crystallizes in the monoclinic system space groupP21/c, witha= 8.0955 (7) Å,b= 22.1988 (18) Å,c= 12.9314 (11) Å;β= 103.4700(10)°;Z= 4;S= 1.01;V= 2260.0(3) Å3;DCalcd= 1.476 gcm–3;F(000) = 1040;μ= 0.92 mm–1;R1= 0.041;wR2= 0.104. The complex2,C23.50H27N5NaNiO5.50, the crystals belong to the monoclinic system, space groupC2/c, witha= 31.553 (8) Å,b= 12.836 (3) Å,c= 13.264 (3) Å;β= 111.234 (4)°;Z= 8;S= 0.95;V= 5007.6 (19)Å3;DCalcd= 1.457 gcm–3;F(000) = 2288;μ= 0.84 mm–1;R1= 0.072;wR2= 0.211. Complexes 1 and 2 are bothaxisymmetricheterobinuclearnickelcomplexes. The geometry around nickel atoms can be described as a slightly distortedplane geometry, andsodium atomsthat as a slightly distorted octahedral geometry. Complexes 1 and 2 are bothone-dimensional (1D) chainlike supramolecular structurebridgedby dicyandiamide to form the polymer. The coordination mode of dicyandiamide is different in both complexes. In 1, the dicyandiamide is μ1,5-dcabridgedcoordination mode; in 2, that is μ1,3-dcabridgedcoordination mode by dicyandiamide. Supplemental materials are available for this article. Go to the publisher's online edition ofSynthesis and Reactivity in Inorganic, Metal-Organic, and Nano-Metal Chemistryto view the supplemental file. [ABSTRACT FROM AUTHOR]

Two hexanuclear cobalt clusters [Co6(bms)12]·(X)6·yH2O (1, X = ,y = 12;2, X = ,y = 8) and one new trinuclear nickel cluster [Ni3S(bms)3]·NO3·C2H5OH (3) (Hbms = (1H-benzoimidazol-2-yl)-methanethiol) have been synthesized and characterized by elemental analysis, IR spectrum, and X-ray single-crystal diffraction. Compound1crystallizes in the trigonal system,Rspace group, and consists of hexanuclear CoIIIunits, which are bridged byμ2-S-benzimidazoles in a square arrangement around cobalt. Compound2crystallizes in the monoclinic system,P21/nspace group, and also consists of hexanuclear CoIIIunits containing the same kind ofμ2-S-benzimidazole bridges like1, but contains different counter anions and lattice waters. Compound3crystallizes in the orthorhombic system,Pbcaspace group, and is composed of trinuclear NiIIunits. These results show that geometries and sizes of the corresponding anions as well as their coordinating mode and hydrogen-bonding properties are important in determining the final structures of the assemblies. [ABSTRACT FROM AUTHOR]

Four anamorphic fungal species of Heteroconium were collected from tropical and subtropical forests in southern China. Among them, Heteroconium tsoongiodendronis sp. nov. and Heteroconium fici sp. nov. are described from specimens collected on dead branches of Tsoongiodendron odorum and Ficus gibbosa, respectively. Two species of Heteroconium, H. decorosum and H. ponapense, are recorded for the first time in China. A key to Heteroconium and related genera is also provided. [ABSTRACT FROM AUTHOR]

Parablastocatena tetracerae gen. et sp. nov. and Corynesporella licualae sp. nov., collected on dead branches of Tetracera asiatica and Licuala fordiana, respectively, in tropical forests of China, are described and illustrated. Parablastocatena tetracerae is the type species for a new monotypic genus in possessing macronematous conidiophores forming distinct synnemata with holoblastic conidiogenesis and euseptate, short-chained conidia ending in a paler brown rostrum, whereas C. licualae is distinguished from described species by the smaller conidia with long appendages. A key to currently accepted species of Corynesporella is provided. [ABSTRACT FROM AUTHOR]