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Under the hydrothermal conditions, the reactions between CuI, KI and bp/bpp (bp=4,4′-bipiperidine, bpp=1,3-bis(4-piperidyl)propane) in an acidic alcohol solution produced three new organically templated iodocuprates(I) as [H2bp]2[Cu2I6] 1, [tmbp][Cu2I4] 2 and [tmbpp] 2 [Cu4I8]·2H2O 3 (tmbp2+=N,N,N′,N′-tetramethyl-4,4′-bipiperidinium; tmbpp2+=N,N,N′,N′-tetramethyl-1,3-bis(4-piperidyl)propane dication). X-ray analysis revealed that (i) tmbp2+ and tmbpp2+ in compounds 2 and 3 originated from the complete N-alklation of bp/bpp with CH3OH; (ii) templated by H2bp2+, the inorganic anion [Cu2I6]2− of 1 possesses a dinuclear structure, whereas templated by tmbp2+, the inorganic anion [Cu2I4]2− of 2 exhibits a one-dimensional (1D) chain structure; (iii) templated by tmbpp2+, the inorganic anion [Cu4I8]4− of 3 shows a cubane-like structure modified by four terminal I− ions. The photoluminescence analysis indicates that compounds 1 and 2 emit blue light, while compound 3 emits green light.

Under the hydro(solvo)thermal conditions, the reactions of metal halides with organic N-heterocyclic molecules produced three new organically modified metal halides [tmbp][Cu2Br4] (tmbp2+ = N,N,N′,N′-tetramethyl-4,4′-bipiperidinium) 1, [H2(dmbpp)][Pb2I6] (dmbpp = dimethyl-1,3-bis(4-piperidyl)propane) 2 and [PbI2(bpp)] 3 (bpp = 1,3-bis(4-pyridyl)propane). It is noteworthy that tmbp2+ in compound 1 originated from the in situ alkylation of bp with CH3OH (bp = 4,4′-bipiperidine). The mechanism study indicates that H+ and Br− play a key role in the alkylation reaction. X-ray single-crystal diffraction analysis revealed that (i) compounds 1 and 2 are the organically templated halometallates. Both possess the 1D chain structures. The 1D chain of compound 1 can be regarded as a linear arrangement of CuBr4 tetrahedra by sharing the edges, whereas that of compound 2 can be considered as an endless extension of PbI6 octahedra by sharing the faces; (ii) compound 3 is the 1:1 adduct of PbI2 and bpp. The PbI2 chain shows a linear shape. Bpp serves as the connector, propagating the PbI2 chains into a 2D layer network of compound 3.

Two kinds of new organic bridging-type ligands 1,4-diazacycloheptane (dach) and 1,3-bis(4-piperidyl)propane (bpp) were used respectively to react with a mixture of CuI and KI under the solvothermal conditions, generating two new 3-D metal–organic frameworks [Cu4I4(dach)2] 1 and [Cu4I4(bpp)2] 2. Both are based on the cubane Cu4I4 clusters as the nodes, but are extended by the different bridging-type ligands into the different topologies. Compound 1 shows a 2-fold interpenetrated quartz-64.82 topology, whereas compound 2 shows a 5-fold interpenetrated diamond-66 topology. The solid-state emission spectra indicate that both contain the photoluminescence properties with maximum emission peaks at 581 nm for 1 and at 616 nm for 2 upon excitation, respectively.

Ischemic stroke is a major cause of morbidity and mortality, yet lacks effective neuroprotective treatments. The aim of this work was to investigate whether treatment with isorhamnetin protected the brain against ischemic injury in mice. Experimental stroke mice underwent the filament model of middle cerebral artery occlusion with reperfusion. Treatment with isorhamnetin or vehicle was initiated immediately at the onset of reperfusion. It was found that treatment of experimental stroke mice with isorhamnetin reduced infarct volume and caspase-3 activity (a biomarker of apoptosis), and improved neurological function recovery. Treatment of experimental stroke mice with isorhamnetin attenuated cerebral edema, improved blood-brain barrier function, and upregulated gene expression of tight junction proteins including occludin, ZO-1, and claudin-5. Treatment of experimental stroke mice with isorhamnetin activated Nrf2/HO-1, suppressed iNOS/NO, and led to reduced formation of MDA and 3-NT in ipsilateral cortex. In addition, treatment of experimental stroke mice with isorhamnetin suppressed activity of MPO (a biomarker of neutrophil infiltration) and reduced protein levels of IL-1β, IL-6, and TNF-α in ipsilateral cortex. Furthermore, it was found that treatment of experimental stroke mice with isorhamnetin reduced mRNA and protein expression of NMDA receptor subunit NR1 in ipsilateral cortex. In conclusion, treatment with isorhamnetin protected the brain against ischemic injury in mice. Isorhamnetin could thus be envisaged as a countermeasure for ischemic stroke but remains to be tested in humans.

Based on the hydrothermal in situ acylation reaction of 4,4′-biphthalic acid (bpha) with N2H4·H2O, a new acylhydrazidate-bridged 1-D chained Cd2+ coordination polymer [Cd(BPTH)(phen)]·3.75H2O (BPTH = 4,4′-biphthalhydrazidate, phen = phenanthroline) was synthesized, and characterized by elemental analysis, infrared spectroscopy, powder X-ray diffraction (XRD), thermogravimetric analysis and single-crystal XRD. With ancillary phen molecules, the BPTH molecules link the Cd2+ centers into a 1-D staircase chain structure of compound 1 based on the Cd2O2 clusters. Based on the hydrothermal in situ acylation reaction of 4,4′-biphthalic acid (bpha) with N2H4·H2O, a new acylhydrazidate-bridged 1-D chained Cd2+ coordination polymer [Cd(BPTH)(phen)]·3.75H2O (BPTH = 4,4′-biphthalhydrazidate, phen = phenanthroline) was synthesized. With ancillary phen molecules, the BPTH molecules link the Cd2+ centers into a 1-D staircase chain structure of compound 1 based on the Cd2O2 clusters.

Under the hydrothermal conditions, the simple self-assemblies of the Pb2+ salts, NaBr/KI and dabco in acidic aqueous solutions created two protonated dabco-templated chained haloplumbates [H2dabco][Pb2Br6]·H2O 1 and [Hdabco][PbI3]·H2O 2 (dabco = 1,4-diazabicyclo[2,2,2]octane). Compound 1 possesses the 1-D double-chain structure based on the Pb2Br9 subunits, while compound 2 shows the simple 1-D single-chain structure based on the PbI6 octahedra. Ultraviolet–visible spectrum analysis indicates that compound 2 is the potential semiconductor material. [Under the hydrothermal conditions, the simple self-assemblies of the Pb2+ salts, NaBr/KI and dabco in acidic aqueous solutions created two protonated dabco-templated chained haloplumbates [H2dabco][Pb2Br6]·H2O 1 and [Hdabco][PbI3]·H2O 2. Compound 1 possesses the 1-D double-chain structure based on the Pb2Br9 subunits, while compound 2 shows the simple 1-D single-chain structure based on the PbI6 octahedra. UV–vis spectrum analysis indicates that compound 2 is the potential semiconductor material.]

By applying the hydrothermal in situ acylation reactions between alkyl-substituted pyridine-2,3-dicarboxylic acids and hydrazine hydrate, six pyridine-monoacylhydrazidate-coordinated transition-metal complexes [Mn(MPDH)2] 1, [M(MPDH)2(H2O)2]·2H2O (M2+ = Co2+ 2, Zn2+ 3), [Mn(EPDH)2(H2O)2] 4 and [M(EPDH)2(H2O)2] (M2+ = Zn2+ 5, Co2+ 6) (MPDH = 6-methylpyridine-2,3-dicarboxylhydrazidate; EPDH = 5-ethylpyridine-2,3-dicarboxylhydrazidate) were obtained. Although only compound 1 is a 1-D chained coordination polymer and the others are the mononuclear molecular entities, they all further self-assemble into the interesting supramolecular networks via hydrogen-bonded interactions between pyridine-monoacylhydrazidate ligands. Two Zn2+ compounds 3 and 5 possess the fluorescence properties with maximum emissions at 517 nm for 3 and 530 nm for 5 upon excitation, respectively. The magnetic analysis for compound 1 indicates there exists the antiferromagnetic interactions between the Mn(II) ions.

In methanol solutions, two types of organic N-donor ligands bta and dabco (bta = benzotriazole; dabco = 1,4-diazabicyclo[2,2,2]octane) were selected to react with CuI under the solvothermal conditions, creating two new copper(I) iodides as one-dimensional (1D) chained [CuI(bta)] 1 and tetranuclear [(mdabco)2Cu4I6] (mdabco = N-methyl-1,4-diazabicyclo[2,2,2]octane). Note that mdabco derived from the solvothermal in situ alkylation reaction between dabco and methanol solvent. The photoluminescence analysis revealed that compound 2 is a potential fluorescence material with maximum emission at 506 nm. The structural characterization of two new copper(I) iodides as chained [CuI(bta)] 1 and tetranuclear [(mdabco)2Cu4I6] (bta = benzotriazole; mdabco = N-methyl-1,4-diazabicyclo[2,2,2]octane) 2 were reported. Mdabco derived from the solvothermal in situ alkylation reaction between dabco and methanol solvent. .

The paper studies the relationship between axial force and breadth of back blade by numerical simulation and experiment. On the basis of the RNG k-ε turbulence model and technology of compact local grids and regional computing, three dimensional numerical simulations to 100HZ165-250 centrifugal pump with various breadths were carried out. Through comparing and analyzing of the flow field, it can be seen that the axial force reduces with the increase of the back blade breadth. After that, the simulation results were verified by the experimental data got from different test devices, and it shows that the conclusions are reliable.

A new type of balance drum with grooves was presented, and analyzed the influence of quantity of grooves on performance of centrifugal pump and balance force by the method of numerical simulation and experiment. The liquid flowing situation at the clearance and the differential pressure on both sides of the balance drum under different quantities of grooves were simulated. The efficiency, quantity of flow and axial force were measured by the experiments with different test devices. After comparing and analyzing the results of simulations and experiments, it indicate that with the increase of grooves the resistance in the clearance increase, the leakage losses reduce, the efficiency of pump enhance and the differential pressure between both sides of the balance drum increase, which contributes to balance the axial force.

In this paper, the method of balancing the axial force with balance hole is studied based on the combination of CFD and experimental research. The relationship between the radial position of balance hole and the effect of axial force and external characteristics of the pump is in-depth studied. Research shows that, there are certain laws for the effect of the balance hole location to the axial force and the external characteristics: the overall pressure of the balance chamber and the axial force decrease with the decrescence of the balance hole radial location, which could get good effect on balancing axial force. But the head and efficiency decreased.

Two types of organic cyclic aliphatic diamine molecules piperazine (pip) and 1,3-bis(4-piperidyl)propane (bpp) were used, respectively, to react with an inorganic mixture of CuI and KI in the acidic CH{sub 3}OH solutions under the solvothermal conditions, generating finally three new organically templated iodocuprates as 2-D layered [(Hpip)Cu{sub 3}I{sub 4}] 1, 1-D chained [tmpip][Cu{sub 2}I{sub 4}] 2 (tmpip=N,N,N',N'-tetramethylpiperazinium) and dinuclear [H{sub 2}bpp]{sub 2}[Cu{sub 2}I{sub 5}] I.2H{sub 2}O 3. Note that the templating agent tmpip{sup 2+} in compound 2 originated from the in situ N-alkylation reaction between the pip molecule and the methanol solvent. The photoluminescence analysis indicates that the title compounds emit the different lights: yellow for 1, blue for 2 and yellow-green for 3, respectively. - Graphical abstract: The solvothermal self-assemblies of CuI, KI and pip/bpp in acidic CH{sub 3}OH solutions created three iodocuprates 2-D layered [(Hpip)Cu{sub 3}I{sub 4}] 1, 1-D chained [tmpip][Cu{sub 2}I{sub 4}] 2 and dinuclear [H{sub 2}bpp]{sub 2}[Cu{sub 2}I{sub 5}] I.2H{sub 2}O 3. Highlights: > A new layered iodocuprate(I) with 20-membered rings was hydrothermally prepared. > A simple approach to prepare the new organic templating agent was reported. > Photoluminescence analysis indicates the emission for iodocuprate(I) is associated with the Cu...Cu interactions.

Under hydrothermal conditions, the simple reactions between metal salts, aromatic polycarboxylic acids (4,4′-diphthalic anhydride ketone, dphahk; 4,4′-sulfoyldiphthalic anhydride, sdpha; pyridine-2,3-dicarboxylic acid, pdca) and N2H4·H2O with or without the presence of phenanthroline·H2O (phen) yielded four di(mono)acylhydrazidate-coordinated Cd2+/Zn2+ compounds as [Cd(DPHKH)(phen)]·1.75H2O 1, [Zn3(DPHKH)2(HDPHKH)2(phen)2]·8H2O 2, [Cd(SDPTH)(phen)(H2O)]·H2O 3 and [Zn(PDH)2(H2O)2] 4 (DPHKH = 4,4′-diphthalhydrazidatoketone hydrazone; SDPTH = 4,4′-sulfoyldiphthalhydrazidate; PDH = pyridine-2,3-dicarboxylhydrazidate). The di(mono)acylhydrazide molecules in the title compounds originated from the hydrothermal in situ acylation reactions of aromatic polycarboxylic acids with N2H4·H2O. It is noteworthy that another kind of hydrothermal in situ reaction was also observed when preparing compounds 1 and 2, namely the nucleophilic addition reaction between the keto group (of dphahk) and N2H4. The photoluminescence analysis indicates that the compounds in the different states (in the solid state or in aqueous solution) may exhibit different emission behaviors.