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Six metal–organic frameworks of [Cd2(L)2(mmpa)2]·6H2O (1), [Mn2(L)2(mmpa)2]·L·2H2O (2), [Zn(L)(NO2 mbda)]·H2O (3), [Cu(L)(NO2 mbda)] (4), [Co3(L)2(BTC)2(H2O)4]·H2O (5), and [Co3(L)2(OBTC)2(H2O)2] (...

A multimode process monitoring method based on multiblock projection nonnegative matrix factorization (MPNMF) is proposed for traditional process monitoring methods which often adopt global model of data and ignore local information of data. Firstly, the training data set of each mode is partitioned by the complete link algorithm and the multivariate data space is divided into several subblocks. Then, the projection nonnegative matrix factorization (PNMF) algorithm is used to model each subspace of each mode separately. A joint probabilistic statistic index is defined to identify the running modes of the process data. Finally, the Bayesian information criterion (BIC) is used to synthesize the statistics of each subblock and construct a new statistic for process monitoring. The proposed process monitoring method is applied to the TE process to verify its effectiveness.

We herein report that the morphology, size, and surface charge status of MIL-100(Fe) micro/nanoparticles can be tailored by adding a coordination modulator (HF or tetramethylammonium hydroxide) to the reaction system. Interestingly, the adsorption capacities of low-crystallinity MIL-100(Fe) and MIL-100(Fe)-TMA toward Congo red (CR) and acid chrome blue K (AC) were found to be significantly larger than that of the high-crystallinity MIL-100(Fe)-HF adsorbent, whereas there was little difference in the adsorption capacities of the three MIL-100(Fe) toward methyl orange (MO) and methylene blue (MB). The adsorption uptake of MIL-100-(Fe)-TMA toward the anionic dyes (CR, AC, and MO) was found to be highest, whereas the adsorption uptake of MIL-100(Fe) toward the cationic dye (MB) was the highest owing to different adsorption mechanisms. This adsorption behavior could be rationalized based on the morphological characteristics and crystal structure defects, zeta potential, and pore volume of MIL-100(Fe) and the a...

Five Cd(II) metal–organic frameworks (MOFs), [Cd(HL)2] (1), [Cd(HL)2(H2O)2] (2), [Cd3(HL)2(obda)2] (3), [Cd2(HL)2(ohmbda)(DMA)(H2O)] (4), and [Cd2(HL)(btc)(H2O)2]·3H2O (5), were prepared by reactions of Cd(NO3)2·4H2O with 1-(1H-imidazol-4-yl)-4-(4H-tetrazol-5-yl)benzene (H2L) or mixed carboxylate ancillary ligands of 1,2-benzenedicarboxylic acid (H2obda), 5-hydroxy-1,3-benzenedicarboxylic acid (H2ohmbda), and 1,3,5-benzenetricarboxylic acid (H3btc), respectively. Their structures have been characterized by single-crystal X-ray diffraction, elemental analysis, infrared spectroscopy (IR), thermogravimetric analysis, and powder X-ray diffraction. Compounds 1 and 2 are supramolecular isomeric frameworks without consideration of the solvent molecules. Complex 1 exhibits a binodal (3, 5)-connected two-dimensional (2D) layer structure with the point (Schläfli) symbol of (52·6)(55·64·7), while complex 2 shows a 2D + 2D → 3D (three-dimensional) framework. Complex 3 is a (3, 5, 6)-connected tetranodal 3D net with the point (Schläfli) symbol of (4·82)2(45·6·84)2(45·65)2(48·66·8). Compound 4 is a (3, 3, 8)-connected trinodal 3D net with the point (Schläfli) symbol based on a binuclear [Cd2N2O] subunit, while 5 is a 2-nodal (3, 4)-connected 2D V2O5-type network based on [Cd2N2(COO)2] SBU. The studies of molecular sensing properties show that the luminescent MOFs can be employed as fluorescent sensors for the detection of Fe3+ and nitro compounds. Compound 1 and 3 exhibit quenching responses for Fe3+ in dimethylformamide solution with detection limits of 2.3 × 10–6 and 8.6 × 10–7 M, respectively. Meanwhile, compound 5 can sense 4-nitrophenol with a detection limit as low as 5.75 × 10–7 M.

Four new metal-organic frameworks [Zn3(HL)2(btc)2(H2O)2]·H2O (1), [Mn(H2L)(btc)(H2O)] (2), [Zn2(L)(HL)(SIP)(H2O)]·4H2O (3) and [Cd(H2L)(SIP)(H2O)]·3H2O (4) were obtained by reactions of the different metal(II) salts with mixed ligands including 1,2,3-benzenetricarboxylic acid (H3btc), sodium 5-sulfoisophthalate (NaH2SIP) and 1-(4-(1H-imidazole-5-yl)phenyl)-1H-1,2,4-triazole (HL), respectively. All compounds were characterized by single-crystal X-ray diffraction, FT-IR spectroscopy, and elemental analysis. The study shows that the natures of organic ligands as well as metal ions play key roles in modulating the resulting frameworks of 1–4. The complex 1 is a (3, 4, 4)-connected three-dimensional (3D) net with the point (Schlafli) symbol of (42·63·8)4(64·8·10), while 2 is a two-dimensional (2D) layer structure referred as fes net with a Point (Schlafli) symbol of (4·82). Complex 3 has 2-nodal (3, 3, 4)-connected rare tfc net with a Point (Schlafli) symbol of (83)2(85·10), while 4 is a supramolecular polymer constructed from infinite one-dimensional (1D) chains by the interaction of rich hydrogen bonds and π - π stacking. The luminescent properties have been investigated for the compounds 1, 3, and 4 containing metal d10 Zn(II) and Cd(II) atoms.

Parkinson's disease (PD) is characterized not only by typical motor symptoms, but also by nonmotor symptoms in the early stages. In addition to the loss of dopaminergic (DAergic) neurons, progressive degenerations of noradrenergic (NA) and serotonergic (5-HT) neurons were also observed. However, the respective effects and interactions of these monoamine depletions on certain nonmotor symptoms are still largely unknown. In the present study, we performed selective depletions of NA, 5-HT and DA in mice by intraperitioneal injection of N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine hydrochloride (DSP-4), 4-chloro-L-phenylalanine (pCPA) and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), respectively. DSP-4 led to a 34% decrease in the number of NAergic neurons in the locus coeruleus, and MPTP led to a 30% decrease in the number of DAergic neurons in the substantia nigra. Although there was no obvious change in the number of 5-HTergic neurons in the dorsal raphe nucleus after pCPA treatment, the levels of 5-HT and its metabolite in the frontal cortex and hippocampus were reduced, respectively. Locomotor activity deficit was induced by DA depletion and a decrease in traveled distance was potentiated by additional NA depletion. Despair-associated depressive-like behavior could be observed in every group. Anxiety states emerged only from the combined depletion of two or three monoamines. However, combined depletion of the three monoamines dramatically induced anhedonia, and it could also aggravate the depressive-like and anxiety behavior. Furthermore, NA depletion significantly reduced spatial learning and memory ability, which was not enhanced by additional 5-HT or DA depletion. Our data highlighted the interactive role of NA, 5-HT and DA in the motor, emotional and cognitive deficits, providing new insight into the complex orchestration of impaired monoaminergic systems that related to the pathology of PD.

SUR1, one of the subunits of ATP-sensitive potassium (KIn this study, we detected the KOur results showed that the mRNA levels of SUR1 subunit were markedly increased by 35% in WT α-Syn overexpression cells and by 31% in A53T α-Syn overexpression cells, respectively. However, the mRNA levels of SUR2B and Kir6.2 subunit have no obviously differences from the controls.We showed that the mRNA levels of SUR1 but not SUR2B or Kir6.2 were selectively upregulated in MES23.5 cells over-expressed with α-Syn. The findings demonstrated that the SUR1 overexpressed might be involved in the process of PD.

Carbon nanofiber (CNF) and silicon carbonitride (SiCN) ceramic nanocomposites (SiCN/CNF) are fabricated by in-situ growth of CNFs in SiCN ceramics during ceramic transformation of polymeric precursors of polysilazanes (PSZ). Metal catalyst precursors are mixed into the polysilazane liquid forming metal particles from decomposition under heating during the pyrolysis. At certain temperatures, ethylene was introduced as a carbon source to induce the growth of CNFs over the metal particles in the ceramic body followed by heating to higher temperatures to complete the pyrolysis. In this way, bulk nanocomposites of SiCN/CNF are obtained as crack-free bodies although some pores are left in the sample. Scanning electron microscopy (SEM) analysis performed on the cross-section of nanocomposites revealed the distribution of needle-like nanofibers of diameter ~ 200 nm and exposed length of ~ 2 μm. The CNFs exhibited the unique multiscale nanostructure in micron hollow tubes with branched nanofiber walls. Energy dispersive X-ray spectrometer (EDX) detected carbon as the major element from the nanofibers confirming the formation of carbon nanofibers. Moreover, clusters of nanoparticles are formed on the ceramic surface from carbon depositions. The in-situ growth of CNFs in SiCN ceramics provides a one-step process potentially to be developed for fabrication of structural and functional SiCN/CNF nanocomposites.

A new coordination polymer, namely, [Cd(L)(frda)(H2O)]&middot, 0.5L&middot, H2O (1) was synthesized by hydrothermal reaction based on mixed multi-N donor 1-(4-(1H-imidazol-5-yl) phenyl)-1H-1,2,4-triazole (L) and O-donor 2,5-furandicarboxylic acid ligands (H2frda) with CdCl2&middot, 2.5H2O. Compound 1 was characterized by single-crystal x-ray diffraction, elemental analysis, and IR spectroscopy. In 1, both the multi-N donor and O-donor frda2&minus, ligands act as linear two-connectors to bridge Cd(II) atoms, forming a two-dimensional (2D) layer. Interestingly, the parallel 2D layers stack in an AAA&middot, &middot, mode, and the infinite one-dimensional (1D) channels formed along the a-axis direction, where the uncoordinated L molecules were embedded in the void. Furthermore, the weak interactions including the rich hydrogen bonding and &pi, &minus, &pi, stacking interactions progress the 2D structure into a three-dimensional (3D) supramolecular polymer. Diffuse reflectance spectra and the luminescent property were also investigated.

Two interpenetrated coordination polymers (CPs) {[Zn1(L)(NO2pbda)]n[Zn2(L)(NO2pbda)]n} (1) and [Zn(L)(Brpbda)]n (2) were prepared by reactions of zinc sulfate heptahydrate with N-donor ligands of 1,4-di(1H-imidazol-4-yl)benzene (L) and auxiliary carboxylic acids of nitroterephthalic acid (H2NO2pbda) and 2,5-dibromoterephthalic acid (H2Brpbda), respectively. The structures of the CPs were characterized by Fourier-Transform Infrared (IR) spectroscopy, elemental analysis, and single-crystal X-ray diffraction. The coordination polymer 1 has two different (4, 4) sql 2D layer structures based on the [Zn(L)(NO2pbda)] moiety, which results in inclined interpenetration with a 2D + 2D &rarr, 3D architecture, while the CP 2 exhibits a 3-fold interpenetrating dmp network. The diffuse reflectance spectra are also investigated for the CPs 1 and 2.

Background: SUR1, one of the subunits of ATP-sensitive potassium (K ATP ) channels, was found to be highly expressed in mRNA levels in the substantia nigra (SN) of Parkinson’s disease (PD) brains. Though the mechanism of the selective dopamine (DA) neurons death is still unknown, some studies have demonstrated that selective activation of the K ATP channels in the SN might be associated with the degeneration of DA neurons. The objective of our study is to examine the expressions of K ATP channel subunits in dopaminergic cells with alpha-synuclein (α-Syn) transfection. Methods: In this study, we detected the K ATP channel subunits mRNA levels in MES23.5 cells by real-time quantitative PCR after the cells transfected with α-Syn. Results: Our results showed that the mRNA levels of SUR1 subunit were markedly increased by 35% in WT α-Syn overexpression cells and by 31% in A53T α-Syn overexpression cells, respectively. However, the mRNA levels of SUR2B and Kir6.2 subunit have no obviously differences from the controls. Conclusions: We showed that the mRNA levels of SUR1 but not SUR2B or Kir6.2 were selectively upregulated in MES23.5 cells over-expressed with α-Syn. The findings demonstrated that the SUR1 overexpressed might be involved in the process of PD.

A continuous cotton-like carbon nanotube fiber yarn, consisting of multiple threads of high purity double walled carbon nanotubes, was fabricated in a horizontal CVD gas flow reactor with water vapor densification by the direct chemical vapor deposition spinning process. The water vapor interaction leads to homogeneous shrinking of the CNT sock-like assembly in the gas flow. This allows well controlled continuous winding of the dense thread inside the reactor. The CNT yarn is quite thick (1-3 mm), has a highly porous structure (99%) while being mechanically strong and electrically conductive. The water vapor interaction leads to homogeneous oxidation of the CNTs, offering the yarn oxygen-functionalized surfaces. The unique structure and surface of the CNT yarn provide it multiple processing advantages and properties. It can be mechanically engineered into a dense yarn, infiltrated with polymers to form a composite and mixed with other yarns to form a blend, as demonstrated in this research. Therefore, this CNT yarn can be used as a "basic yarn" for various CNT based structural and functional applications.