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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]

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]

Background: Mucocutaneous lesions are common features of primary Sjögren's syndrome (pSS), but only a few studies have focused on them. To demonstrate the profile of mucocutaneous lesions of pSS and further explore their potential clinical significance, we performed a cross-sectional study on 874 patients., Methods: Demographic data, clinical manifestations, and laboratory results of 874 pSS patients were collected. Patients were divided into two groups according to the presence of mucocutaneous lesions. Differences in primary symptoms and systemic impairments between the two groups were analyzed. Results of laboratory tests were also compared after excluding those who had taken corticosteroid from both groups. One-year follow-up was done, and occurrences of various new complications were compared., Results: Among the 874 pSS patients, 181 patients had mucocutaneous lesions, accounting for 20.7%. Multiple mucocutaneous manifestations were displayed, and the top four most common types of lesions were purpuric eruptions (39.8%), urticaria (23.8%), Raynaud's phenomenon (14.9%), and angular stomatitis (9.9%). Incidences of pulmonary interstitial fibrosis, pulmonary bullae, leukopenia, and anemia were significantly higher among patients with mucocutaneous lesions (P < 0.05). Increase in IgG and decrease in C4 among patients with mucocutaneous lesions displayed statistical significance after excluding patients from both groups who had taken corticosteroid (P < 0.05). After one-year follow-up, patients with mucocutaneous lesions presented a slightly higher incidence of new complications compared to those without., Conclusions: Mucocutaneous manifestations of pSS patients were common and diverse. Patients with mucocutaneous manifestations had more systemic damages, higher level of IgG, and lower level of serum C4, suggesting a higher activity of the primary disease.

Aim: To evaluate the clinical and optical outcomes after clear corneal incision cataract surgery (CICS) with three different incision sizes (1.8, 2.0 and 3.0 mm)., Methods: Eyes of 150 patients with age-related cataract scheduled for coaxial cataract surgery were randomized to three groups: 1.8, 2.0, or 3.0 mm CICS. Intraoperative data and postoperative outcomes including surgically induced astigmatism (SIA), the corneal incision thickness, wavefront aberrations and modulation transfer function (MTF) of cornea were obtained., Results: There were no significant differences among the three groups in demographic characteristics and intraoperative outcome. The 1.8 and 2.0 mm microincisions showed more satisfactory clinical outcomes than the 3.0 mm incision. The 1.8 mm incision showed significantly less SIA than the 2.0 mm incision until postoperative 1mo (P<0.05), but the difference was only 0.14-0.18 D. Combined with less increased incision thickness only at postoperative 1d (P=0.013), the 1.8 mm incision presented better uncorrected distance visual acuity (UCDVA) than the 2.0 mm incision only at 1d postoperatively (P=0.008). For higher-order aberrations and other Zernike coefficients, there were no significant differences between the 1.8 mm group and 2.0 mm group (P>0.05)., Conclusion: Converting from 3.0 mm CICS to 1.8 or 2.0 mm CICS result in better clinical and optical outcomes. However, when incision is 1.8 mm, the benefits from further reduction in size compared with 2.0 mm are limited. The necessity to reduce the incision size is to be deliberated.

The title complex, [Co(C(10)H(9)N(4)O(2)S)(2)(C(3)H(7)NO)(2)], lies across an inversion center. The Co(II) atom is coordinated in a slightly distorted octa-hedral geometry by four N atoms from two bidentate 4-amino-N-(pyrimidin-2-yl)benzene-sulfonamidate (sulfadiazine) anions and two O atoms from two dimethyl-formamide (DMF) ligands. The dihedral angle between the benzene and pyrimidine rings is 82.37 (13)°. A three-dimensional network is generated by N-H⋯O hydrogen bonds between the amino groups and of the sulfonamidate O atoms of neighbouring mol-ecules. The DMF ligand is disordered over two sets of sites in a 0.559 (4):0.441 (4) ratio.

The asymmetric unit of the title compound, [Co(C(9)H(8)Cl(2)NO)(3)], contains three independent mol-ecules. In each mol-ecule, the Co(III) ion is coordinated by an O atom and an N atom from three bidentate 2,4-dichloro-6-(ethyl-imino-meth-yl)phenolate ligands in a slightly distorted octa-hedral environment. In the crystal, a weak C-H⋯Cl hydrogen bond is observed.

In the title complex, [Ni(C(9)H(9)BrNO)(2)], the Ni(II) ion lies on an inversion centre and is coordinated in a slightly distorted square-planar geometry by two N atoms and two O atoms from two symmetry-related bidentate 4-bromo-2-(ethyl-imino-meth-yl)phenolate ligands. The complex forms a one-dimensional chain in the crystal structure through short C-H⋯Br contacts (H⋯Br = 3.009 Å).

By a simple and facile wet-chemistry technique without any surfactant, various shapes of Ag(2)S crystals--including leaflike pentagonal nanoplates, crinkly nanoscrolls, hexagonal prismlike microtubes, and microrods--were fabricated in situ on a large-area silver-foil surface separately. Detailed experiments revealed that the Ag(2)S nanoplates were formed just by immersing the silver foil in a sulfur/ethanol solution at room temperature and atmospheric pressure, and they subsequently rolled into nanoscrolls and further grew into microtubes and microrods under solvothermal conditions. Inspired by the natural curling of a piece of foliage, we proposed a surfactant-free rolling mechanism to interpret the observed morphological evolution from lamellar to tubular structures. Based on these simple, practical, and green chemical synthetic routes, we can easily synthesize lamellar, scrolled, tubular, and clubbed Ag(2)S crystals by simply adjusting the reaction temperature, pressure, and time. It is very interesting to note that the current rolling process is quite different from the previous reported rolling mechanism that highly depends on the surfactants; we revealed that the lamellar Ag(2)S could be rolled into tubular structures without using any surfactant or other chemical additives, just like the natural rolling process of a piece of foliage. Therefore, this morphology-controlled synthetic route of Ag(2)S crystals may provide new insight into the synthesis of metal sulfide semiconducting micro-/nanocrystals with desired morphologies for further industrial applications. The optical properties of the pentagonal Ag(2)S nanoplates/film were also investigated by UV/Vis and photoluminescence (PL) techniques, which showed large blue-shift of the corresponding UV/Vis and PL spectra., (Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Background: 17beta-estradiol (E2) has been implicated to exert neuroprotective effects in the brain following cerebral ischemia. Classically, E2 is thought to exert its effects via genomic signaling mediated by interaction with nuclear estrogen receptors. However, the role and contribution of extranuclear estrogen receptors (ER) is unclear and was the subject of the current study., Methodology/principal Findings: To accomplish this goal, we employed two E2 conjugates (E2 dendrimer, EDC, and E2-BSA) that can interact with extranuclear ER and exert rapid nongenomic signaling, but lack the ability to interact with nuclear ER due to their inability to enter the nucleus. EDC or E2-BSA (10 microM) was injected icv 60 min prior to global cerebral ischemia (GCI). FITC-tagged EDC or E2-BSA revealed high uptake in the hippocampal CA1 region after icv injection, with a membrane (extranuclear) localization pattern in cells. Both EDC and E2-BSA exerted robust neuroprotection in the CA1 against GCI, and the effect was blocked by the ER antagonist, ICI182,780. EDC and E2-BSA both rapidly enhanced activation of the prosurvival kinases, ERK and Akt, while attenuating activation of the proapoptotic kinase, JNK following GCI, effects that were blocked by ICI182,780. Administration of an MEK or PI3K inhibitor blocked the neuroprotective effects of EDC and E2-BSA. Further studies showed that EDC increased p-CREB and BDNF in the CA1 region in an ERK- and Akt-dependent manner, and that cognitive outcome after GCI was preserved by EDC in an ER-dependent manner., Conclusions/significance: In conclusion, the current study demonstrates that activation of extranuclear ER results in induction of ERK-Akt-CREB-BDNF signaling in the hippocampal CA1 region, which significantly reduces ischemic neuronal injury and preserves cognitive function following GCI. The study adds to a growing literature that suggests that extranuclear ER can have important actions in the brain.