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Cellulose acetate (CA) grafted with imidazole ionic liquids (CA-ILs) was synthesized by reacting CA with imidazole ionic liquids ([HO2CMmim]Cl, [HO2CEtmim]Cl, and [HO2CMmim]Br) by using tetrahydrofuran (THF) as the solvent and pyridine as the catalyst. The CA and CA-IL films were fabricated by using the casting solution method. The CA-IL films exhibited good film forming ability and mechanical properties. The successful grafting of CA with imidazole ionic liquids was confirmed by Fourier transform infrared (FTIR), 1H NMR, scanning electron microscopy (SEM), and elemental analysis, and the grafting degrees were 2.24, 2.45, and 3.30%, respectively. The CO2 permeation properties of the CA-IL films were 65.5, 105.6, and 88.3 Barrer, increased up to 2.0, 3.2, and 2.7 times, respectively, as compared to pure CA (32.6 Barrer). The CO2/CH4 selectivities of the CA-IL films were 15.6, 12.6, and 19.2, increased up to 1.7, 1.4, and 2.1 times, respectively, as compared to pure CA (9.26). Therefore, it can be concluded that the imidazole ionic liquids are immensely useful for improving the gas separation performance of CA films.

This paper reports the use of rhodium (Rh) catalysts for the oxidative coupling reaction between phenylacetylene and benzaldehyde derivatives via C-H bond activation. These reactions were catalyzed by Rh(l-amino acid)(cod) (the l-amino acid is l-phenylalanine, l-valine or l-proline; cod is 1,5-cyclooctadiene) to obtain chromones in 12.7–88.3% yield. These new Rh catalysts have excellent activity for the coupling reaction between phenylacetylene and different benzaldehyde derivatives. It was found that the electronic effects of the benzaldehyde derivative substituent affected the reaction yield, which is in accordance with the proposed mechanism.

As enantioselectively permeable membrane materials showing high permeability and good self-membrane forming ability, 24 well-defined chiral graft copolymers (PPA-graft-OMPS) consisting of flexible ...

In recent years, much progress has been made in elucidating the functional roles of plant glycine-rich RNA-binding proteins (GR-RBPs) during development and stress responses. Canonical GR-RBPs contain an RNA recognition motif (RRM) or a cold-shock domain (CSD) at the N-terminus and a glycine-rich domain at the C-terminus, which have been associated with several different RNA processes, such as alternative splicing, mRNA export and RNA editing. However, many aspects of GR-RBP function, the targeting of their RNAs, interacting proteins and the consequences of the RNA target process are not well understood. Here, we discuss recent findings in the field, newly defined roles for GR-RBPs and the actions of GR-RBPs on target RNA metabolism.

A pectin/chitosan matrix-loaded curcumin film (PCCF) with a deep eutectic solvent (DES) as the solvent and plasticizer was prepared in this study. Different quantities of curcumin (identified as PCCF-0, PCCF-1, PCCF-2. PCCF-3) were loaded on the pectin/chitosan film in order to evaluate their effects on the film properties. Results showed that curcumin could interact with the pectin/chitosan matrix and form a complex three-dimensional network structure. PCCF could promote the thickness, tensile strength, thermal properties, antioxidant and antiseptic capacities, but deteriorate the light transmission and elongation at the same time. The addition of curcumin would change the color of the film, without significantly affecting the moisture content. The tensile strength of PCCF-3 reached the maximum value of 3.75 MPa, while the elongation decreased to 10%. Meanwhile, the water-resistance properties of PCCF-3 were significantly promoted by 8.6% compared with that of PCCF-0. Furthermore, PCCF showed remarkable sustained antioxidant activities in a dose-dependent manner. PCCF-3 could inhibit DPPH and ABTS free radicals by 58.66% and 29.07%, respectively. It also showed antiseptic capacity on fresh pork during storage. Therefore, curcumin addition could improve the barrier, mechanical, antioxidant and antiseptic properties of the polysaccharide-based film and PCCF has the potential to be used as a new kind of food packaging material in the food industry.

Corn straw is an agricultural waste. The system for extracting cellulose from corn straw at a high temperature has been widely reported by researchers. However, the system for extracting cellulose from corn straw at a low temperature has been rarely reported. In this paper, a new system for extracting cellulose from corn straw at a low temperature was reported for the first time. This new system is designated as the low temperature laccase system (LTLS). Cellulose was successfully extracted from corn straw by the LTLS, and the used solution could be recycled. Therefore, the low temperature laccase system is an environmentally-friendly system. The cellulose content in corn straw is 30&ndash, 40%. The yield of cellulose extracted by LTLS was 33%. The obtained cellulose product was creamy white. The extracted cellulose samples were characterized by using infrared spectroscopy (IR), thermogravimetry (TG), and X-ray diffraction (XRD). The results were consistent with that of standard cellulose. We confirmed that the LTLS extracted cellulose from corn straw with high purity.

Small RNAs are significant regulators of gene expression, which play multiple roles in plant development, growth, reproductive and stress response. It is generally believed that the regulation of plants’ endogenous genes by small RNAs has evolved from a cellular defense mechanism for RNA viruses and transposons. Most small RNAs have well-established roles in the defense response, such as viral response. During viral infection, plant endogenous small RNAs can direct virus resistance by regulating the gene expression in the host defense pathway, while the small RNAs derived from viruses are the core of the conserved and effective RNAi resistance mechanism. As a counter strategy, viruses evolve suppressors of the RNAi pathway to disrupt host plant silencing against viruses. Currently, several studies have been published elucidating the mechanisms by which small RNAs regulate viral defense in different crops. This paper reviews the distinct pathways of small RNAs biogenesis and the molecular mechanisms of small RNAs mediating antiviral immunity in plants, as well as summarizes the coping strategies used by viruses to override this immune response. Finally, we discuss the current development state of the new applications in virus defense based on small RNA silencing.

Novel graft copolymers consisting of rigid poly(substituted acetylene) as a main chain and flexible linear oligodimethylsiloxane (ODMS) as grafts have been synthesized from well-defined macromonomers which were synthesized by living polymerization. The length and the content of ODMS in these graft copolymers have been controlled. The graft copolymers had high molecular weights, good solubility, and good membrane forming ability. Surprisingly the graft copolymers containing the linear ODMSs of more than 80% still had good membrane forming ability. In addition, more surprisingly both permeabilities( P O 2 ) and permselectivities( P O 2 / P N 2 ) for some of the graft copolymers having higher content of ODMS were higher than those for cross-linked PDMS.

Cis-cisoidal poly(substituted phenylacetylene)s have poor membrane forming ability. To solve this problem, we synthesized and polymerized three phenylacetylenes having a silicon-containing substitu...

Six new silicon-containing phenylacetylenes having short oligosiloxane substituents with different sizes and shapes have been synthesized. Homopolymerization of the monomers yielded the corresponding homopoly(substituted phenylacetylene)s with high molecular weights and good solubility. These comb-shaped homopolymers gave self-standing membranes whose P O 2 and P O 2 / P N 2 could be measured. We discuss the effect of the chemical structures on their membrane performances together with the other seven related polymers we synthesized before and commercially available cross-linked polydimethylsiloxane (PDMS). While the homopolymers with linear oligodimethylsiloxanes (ODMS) show very high P O 2 values which are higher than PDMS, the homopolymers with branched ODMS show high P O 2 / P N 2 values which are close to that of poly(phenylacetylene) (poly(PA)) and, in addition, had ten times higher P O 2 than poly(PA). Introduction of the branched spherical ODMS substituents increases P O 2 without any drop of P O 2 / P N 2 and introduction of the linear ODMS substituents increases P O 2 largely which is higher than that of PDMS. It was found that the chemical structures, i.e., the shapes of the ODMS substituents were more important than that of composition for determining their performance as oxygen permselective membrane materials. In conclusion, oxygen permeation could be tuned by changing sizes and shapes of the ODMS side groups.

Zr-based bulk metallic glasses (BMGs) exhibit good mechanical performance and excellent bio-compatibility. However, their high-tech application is limited due to that they are susceptible to chloride ion induced pitting corrosion. Herein, the corrosion behavior and the corresponding mechanism of the Zr65Cu17.5Al7.5Ni10-xCox (x = 0, 2, 4, 6) BMGs in the 3.5% NaCl solution were investigated. The Ni substitution by Co can contribute to significant improvements in the corrosion resistance of the Zr-Cu-Al-Ni BMG. The typical corrosion parameters such as the pitting potential and the pitting overpotential were increased from −199 and 40 mV (x = 0) to −78 and 117 mV (x = 6), respectively. Importantly, the corrosion current density was drastically decreased from 5.8 × 10−6 (x = 0) to 3.2 × 10−7 A/cm2 (x = 6). The electrochemical impedance spectroscopy results demonstrated a distinct increase of the charge transfer resistance from 1.8 × 105 (x = 0) to 8.4 × 105 Ω·cm2 (x = 6). The elemental analysis indicated that the Co substitution could facilitate the formation of stable passivation layer against chloride ion corrosion.

A series of experiments were conducted to characterize the anti-/de-icing performances of soft PDMS materials with different shear modulus and to explore their potentials for aircraft icing mitigation. In the present study, a new class of soft PDMS materials with adjustable shear modulus were fabricated by adding different amounts and different molecular weights of non-reactive trimethyl-terminated PDMS (t-PDMS) into the hydrosilylation mixture of vinyl-terminated PDMS (v-PDMS) and hydride-terminated PDMS (h-PDMS). While the soft PDMS materials were found to be hydrophobic with the contact angle of water droplets over the PDMS surfaces being about 110°, the ice adhesion strength over the soft PDMS materials was found to be extremely low (i.e., being less than 10 kPa at −5 °C or two orders of magnitude smaller), in comparison to those of the conventional rigid surface (i.e., being greater than 1000 kPa for Aluminum or the hard plastic material used to make the airfoil/wing model used in the present study). Upon the dynamic impacting of water droplets at relatively high weber number levels pertinent to aircraft inflight icing phenomena (e.g., We = 4000), the soft PDMS surfaces were found to deform dynamically due to the elastic nature of the PDMS materials, which cause the soft PDMS materials acting as “trampolines” to bounce off most of the impinged water mass away from the impacted surfaces. By applying the soft PDMS materials to coat/cover the surface of a NACA 0012 airfoil/wing model, an explorative study was also performed in an Icing Research Tunnel available at Iowa State University (i.e., ISU-IRT) to demonstrate the feasibility of using the soft PDMS materials to mitigate the impact ice accretion process pertinent to aircraft inflight icing phenomena.

A novel peroxy group-containing silane coupling agent was synthesized and anchored on the surface of titanium dioxide nanoparticles (nano-TiO2) to form an immobilized-initiator-modified nano-TiO2 species. In this study, the kinetic parameters of the peroxy group-containing silane were tested and assessed using DSC. The pre-exponential factor (Ad) was 8.973 × 108 and the activation energy (Ea) was 80.736 kJ mol−1. Moreover, the empirical Arrhenius equation was determined to be ln Kd = − 80.736/RT + ln(8.973 × 108). To obtain continuous polymers, acrylonitrile (AN) and methyl methacrylate (MMA) were polymerized using the novel peroxy group-containing silane and FeSO4 as an initiator system. The number average molecular weights (Mn of PAN = 3×104 and Mn of PMMA = 1.4 × 105) and polydispersity indexes (PDI of PAN = 2.76 and PDI of PMMA = 1.65) were determined by GPC. It was suggested that the redox initiation system can generate highly reactive species on the surfaces of inorganic nanoparticles. The nano-TiO2-grafted polymers were successfully obtained.

Mn2SiO4/CNT composite, which is constructed with polyhedron-shaped particles embedded in the carbon nanotube (CNT) network, has been synthesized by a sol–gel method. The as-prepared Mn2SiO4 presented a well-developed orthorhombic crystal structure, and after modified with CNT, the compound exhibited excellent rate capability and cyclic performance as anode materials for lithium ion batteries. Galvanostatic charge–discharge measurements demonstrated outstanding initial charge and discharge capacity of 664.8 and 392.1 mA h g−1 at the current density of 100 mA g−1, respectively, and stable reversible capacity of 466.9 mA h g−1 was retained after 40 cycles. Even at a high current density of 2000 mA g−1, Mn2SiO4/CNT can deliver the specific capacity of 205.8 mA h g−1. Also, the reaction mechanism of this material is speculated including the formation of Li2SiO3, MnO and Mn. In addition, the significant change of charge transfer resistance compared with pristine Mn2SiO4 confirmed by electrochemical impedance spectroscopy illustrated the fast Li ions intercalation kinetics and reduced electrochemical polarization via CNT modification, suggesting Mn2SiO4/CNT to be promising anode materials for high performance lithium ion batteries.

Premature failure of copper tubes used in air-conditioning units is a serious problem for air conditioning manufacturers and customers. Several failure theories were put forward, such as ant nest corrosion and inter-granular stress corrosion. A new opinion is raised in this article that the interaction of ant nest corrosion and stress corrosion cause the failure of copper tubes. This article analyzes the interactive effect through comparing the morphologies of the failure copper tubes in practical application with the samples which were exposed to the concentration of 1 vol% formic acid vapor in airtight glass vessels for different days. The experiment results show that most of copper failures result from the interactive corrosion due to the morphology of interactive corrosion tunnels is thinner than single ant nest corrosion and the corrosion starting points of interactive corrosion tend to distribute at the bottom of internal groove where the tensile stress was concentrated.

By regulating the order of monomer addition, four kinds of copolymer polyimides (PIs) were prepared using diethylene glycol dimethyl ether (DEGDE) and N, N-dimethylacetamide (DMAc) as the solvents. The molecular weights of polyamide acids (PAAs) ranged from 3.8 × 105 to 9.2 × 105. All of the films displayed high glass transition temperatures ( Tgs) ranging from 313°C to 346°C. The polymer films show excellent thermal stabilities with 5% weight loss at temperatures of 505–524°C and char yields at 800°C were as high as 55% under nitrogen. The peel strengths of flexible copper (Cu) clads were in the range from 0.337 N cm−1 to 0.598 N cm−1. Compared to the molecular weight and peel strength of fresh PAA, those of PAAs prepared using DMAc significantly decreased after storage for 3 months at 0°C. However, when DEGDE was used as the solvent, the molecular weights of the PAAs and the thermal properties of the PIs were maintained after long storage time.

A series of bi-continuous and uniform nanoporous structures were fabricated successfully through chemical dealloying from quaternary Zr65Cu17.5Fe10Al7.5 amorphous ribbons in hydrofluoric acid (HF) solutions under a free corrosion condition. Nanoporous structures obtained from dealloying amorphous ribbons for 5 h in 0.02 M,0.035 M and 0.05 M HF solutions have mean pore sizes of 30–40 nm. A three-dimensional bi-continuous nanoporous copper (NPC) structure formed on Zr65Cu17.5Fe10Al7.5 ribbon alloys has pore sizes of 44.91 nm,52.60 nm and 57.37 nm, respectively, after immersion in 0.02 M HF solution for 15 h, 20 h, and 25 h. It shows that the pore size of NPC structure increases with increasing the dealloying time. The cyclic voltammetry (CV) results reveal that all NPC structures have the obvious electrocatalytic ability to the oxidation of (CH2OH)2 solution, compared with the initial amorphous ribbon without oxidation peak on CV curve. Zr-Cu-Fe-Al amorphous alloys can be new candidates for fabricating NPC structures.

Zr-based bulk metallic glasses have been considered as promising engineering materials. However, their widespread application is limited by their contrasting properties of glass-forming ability (GFA) and plasticity. Herein, the effects of Ni substitution by Co on the GFA and plasticity of the representative Zr-based metallic glass of Zr 65 Cu 17.5 Al 7.5 Ni 10 were investigated. A series of Zr 65 Cu 17.5 Al 7.5 Ni 10 − x Co x (x = 0, 2, 4, 6, 7, 8, 10) rod samples with 2 mm in diameter were prepared by injection copper mold casting method. Amorphous structure was successfully achieved when the Co content is less than 8 at.%. Importantly, the Co addition contributed to significant enhancements in both GFA and plasticity of the amorphous Zr 65 Cu 17.5 Al 7.5 Ni 10 − x Co x (x = 0, 2, 4, 6, 7) alloys. The as-prepared Zr 65 Cu 17.5 Al 7.5 Ni 8 Co 2 amorphous alloy shows the best and attractive performance with a supercooled liquid region width of 80 K and a compressive plasticity of 7.4%, which are much higher than 50 K and 0.2% of the pristine Zr 65 Cu 17.5 Al 7.5 Ni 10 amorphous alloy, demonstrating that the Co substituted Zr-Al-Ni-Cu metallic glass has the potential to be used for engineering applications.

A coupling reaction between salicylaldehyde and phenylacetylene was catalyzed by well-defined rhodium complexes, Rh(cod)(l-amino acid) (cod is 1,5-cyclooctadiene; l-amino acid is l-proline, l-phenylalanine and l-valine), to give a flavonoid in 40–88% yield, providing a method for flavonoid synthesis. The coupling reactions catalyzed by Rh(cod)(l-amino acid)s gave higher yields than those by [Rh(cod)Cl]2 without l-amino acid ligands. The reaction mechanism may be that l-amino acid ligands of the rhodium complexes can provide an empty track for phenylacetylene to form a ring structure that fractures to produce the aim flavonoid and RhIX species. Then, the active RhIX specie is oxidized to regenerate RhIIIX3 by Cu(OAC)2.

The main objective of the paper is to improve the plasticity and reduce the toxicity of the known Zr65Cu17.5Ni10Al7.5 alloy. A series of rod samples with diameter of 2 mm Zr65Cu17.5Al7.5Ni10–xFex (x = 0, 2, 4, 6, 8, 10) were prepared by injection copper mold casting method. Appropriate addition of Fe can enhance GFA of the base alloy significantly. In addition, compared with the base alloy revealing no plastic deformation, partial substitution of Ni by Fe can also improve the compressive plasticity (ep) of alloys effectively. The enhanced plasticity of alloys can be attributed to the positive heat of mixing between Fe and Cu atoms. Alloy with 6% Fe exhibits the relatively good comprehensive properties, as a result of an excellent combination of both good GFA (ΔTx = 81 K) and remarkable plasticity (ep = 6.2%). Zr65Cu17.5Fe10Al7.5 metallic glass is environmentally friendly and has large deformation plasticity, making it a promising candidate for engineering applications.

Ethyl cellulose was grafted with ionic liquids in optimal yields (62.5&ndash, 64.1%) and grafting degrees (5.93&ndash, 7.90%) by the esterification of the hydroxyl groups in ethyl cellulose with the carboxyl groups in ionic liquids. In IR spectra of the ethyl cellulose derivatives exhibited C=O bond stretching vibration peaks at 1760 or 1740 cm&minus, 1, confirming the formation of the ester groups and furnishing the evidence of the successful grafting of ethyl cellulose with ionic liquids. The ethyl cellulose grafted with ionic liquids could be formed into membranes by using the casting solution method. The resulting membranes exhibited good membrane forming ability and mechanical properties. The EC grafted with ionic liquids-based membranes demonstrated PCO2/PCH4 separation factors of up to 18.8, whereas the PCO2/PCH4 separation factor of 9.0 was obtained for pure EC membrane (both for CO2/CH4 mixture gas). The membranes also demonstrated an excellent gas permeability coefficient PCO2, up to 199 Barrer, which was higher than pure EC (PCO2 = 46.8 Barrer). Therefore, it can be concluded that the ionic liquids with imidazole groups are immensely useful for improving the gas separation performances of EC membranes.

Corn stalk was used as the initial material to prepare a corn stalk matrix-g-polyacrylonitrile-based adsorbent. At first, the corn stalk was treated with potassium hydroxide and nitric acid to obtain the corn stalk-based cellulose (CS), and then the CS was modified by 2-bromoisobutyrylbromide (2-BiBBr) to prepare a macroinitiator. After that, polyacrylonitrile (PAN) was grafted onto the macroinitiator by single-electron transfer living radical polymerization (SET-LRP). A novel adsorbent AO CS-g-PAN was, therefore, obtained by introducing amidoxime groups onto the CS-g-PAN with hydroxylamine hydrochloride (NH 2 OH · HCl). FTIR, SEM and XPS were applied to characterize the structure of AO CS-g-PAN. The adsorbent was then employed to remove Pb(II) and Cu(II), and it exhibited a predominant adsorption performance on Pb(II) and Cu(II). The effect of parameters, such as temperature, adsorption time, pH and the initial concentration of metal ions on adsorption capacity, were examined in detail during its application. Results suggest that the maximum adsorption capacity of Pb(II) and Cu(II) was 231.84 mg g –1 and 94.72 mg g −1 , and the corresponding removal efficiency was 72.03% and 63%, respectively. The pseudo-second order model was more suitable to depict the adsorption process. And the adsorption isotherm of Cu(II) accorded with the Langmuir model, while the Pb(II) conformed better to the Freundlich isotherm model.

The reverse atom transfer radical polymerization (RATRP) of acrylonitrile (AN) was carried out in N, N-dimethylformamide (DMF) with AIBN as initiator, FeCl3•6H2O/triphenylphosphine (PPh3) and FeCl3•6H2O/pentamethyldle-thylenetrlamlne (PMDETA) as catalytic systems, respectively. Effect of reaction time and initiator concentration on polymerization rate, molecular weight and molecular weight distribution were investigated in detail. The Fourier transform infrared spectrometer (FTIR) and 1H nuclear magnetic resonance spectroscopy (1HNMR) were employed to analyze the chain end of the PAN. Gel permeation chromatography (GPC) was applied to measure the molecular weight and polydispersity index (PDI) of PAN. The polymerization demonstrated a typical pseudo first-order kinetics characteristics as evidenced by the number-average molecular weights (Mn) increasing linearly with monomer conversion; the Mn decreasing with the increasing of the initiator concentration. Meanwhile, the low PDI value (

Predictions of prospectivity based on remote sensing were developed using alteration mineral indicative hyperspectral mapping and remote sensing anomaly filtering, combined with geological characteristics and anomalous mineral field verification. Based on the results of the hyperspectral mineral mapping and the actual geological ground conditions, the results of mapping of altered minerals, such as chlorite, muscovite, kaolinite, and iron oxide were validated, and gold, silver, copper, nickel, and other geochemical anomaly areas were identified for verification work. The results of hyperspectral mineral extraction show that the mineral assemblage closely related to gold deposits in shear zones is muscovite + chlorite + epidote + kaolinite. This alteration mineral assemblage can be used as regional search criteria for shear zone gold mineralisation and was the basis for the discovery of mineralised hydrothermal alteration centres and delineation of four prospective targets. Established on a spectral prospectivity model of the study area, prospective ore-bearing areas have been delineated, which indicate the direction for further geological and mineral resource surveys.

Recent studies have shown that activation of peroxisome proliferators activated receptor-γ (PPAR-γ) ameliorates renal interstitial fibrosis (RIF) in animal model. Yet, the underlying molecular mechanisms remain still largely unknown. Here, we investigated the hypothesis that activation of PPAR-γ regulates renal remodeling by modulating proliferation of primary cultured renal fibroblasts. In our present study, platelet-derived growth factor-AA (PDGF-AA), a key isoform of PDGF superfamily as mitogen in RIF, was applied to stimulate renal fibroblasts, the selective inhibitor or sequence specific siRNA of PI3K, skp2 or PPAR-γ was used to investigate the involvement of above molecular mediators in PDGF-AA-induced cell proliferation. Our results demonstrate that PDGF-AA induced proliferation of renal fibroblasts by activating PI3K/AKT signaling and resultant skp2 production. Pre-stimulation of cells with rosiglitazone or adenovirus carrying PPAR-γ cDNA (AdPPAR-γ) blocked PDGF-AA-stimulated cell proliferation, this effect was particularly coupled to PPAR-γ inhibition of AKT phosphorylation and skp2 expression. Inhibition of PPAR-γ by GW9662 restored the suppression of activated PPAR-γ on phosphorylation of AKT and subsequent skp2 production. Our results indicate that activation of PI3K/AKT signaling and resultant skp2 generation mediated PDGF-induced proliferation of renal fibroblasts. Activation of PPAR-γ inhibited cell proliferation by inhibition of AKT phosphorylation and its down-streams.

Two novel chiral well-defined rhodium complexes, Rh(cod)(L-Phe) (cod = 1,5-cyclooctadiene, Phe = phenylalanine) and Rh(cod)(L-Val) (Val = valine) were synthesized, isolated by recrystallization, and characterized. The helix-sense-selective polymerization (HSSP) of an achiral 3,4,5-trisubstituted phenylacetylene, p-dodecyloxy-m,m-dihydroxyphenylacetylene (DoDHPA) was examined by using the two Rh complexes as catalysts. These catalysts provided high molecular weight polymers (Mw 28 × 104−45 × 104) in about 40%–85% yields. The resulting polymers exhibited a bisignated CD signal at about 300 nm and a broad signal around 470 nm, indicating that they have preferential one-handed helical structure. The present catalysts achieved larger molar ellipticity up to [θ]310 = 13.0 × 104 deg cm2/dmol than those with binary chiral catalytic systems, [Rh(cod)Cl]2/(L-phenylalaninol), [Rh(cod)Cl]2/(L-valinol), and [Rh(nbd)Cl]2/(R)-PEA. All these results manifest that the present, well-defined Rh complexes serve as excellent catalysts for the HSSP of DoDHPA. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016, 54, 2346–2351

In order to develop a new silane coupling agent that can be used as coupling agent and initiator, (3-(tert-butylperoxy)propyl)trimethoxysilane was synthesized by using tert-butyl hydroperoxide and (3-chloropropyl) trimethoxysilane. The new reagent was characterized by 1H-NMR, FT-IR and mass spectroscopy. The thermokinetics of the new reagent was investigated, including thermal stability, decomposition constants (Kd), activation energy (Ea), the heat of decomposition (ΔH) and pre-exponential factor (Ad). In addition, the application of (3-(tert-butylperoxy)propyl)trimethoxysilane on modificating nano-TiO2 and initiating polymerization was studied. The structures of the products of modificating nano-TiO2 and initiating polymerization were verified by XPS, FT-IR. The results indicated that the new reagent had the characteristics of a coupling agent and initiator.

Iron oxide (Fe2O3) is an intriguing anode material of electrochemical energy storage systems such as rechargeable batteries. The rational design of its nanostructure at mild condition to cope with the issues of low reversible capacity and sluggish kinetics is required. Herein, an efficient, facile, and potentially large-scale synthesis approach using the precursor of laminated iron oxychloride@polyaniline heterostructure and mild annealing is developed, yielding unique Fe2O3@carbon nanocomposites with hematite nanoparticles (∼20 nm) that embedded in nitrogen/chlorine-doped carbon nanodisk (N/Cl–C). Given the benefit of abundant active sites, good chemical contact between carbon and Fe2O3, and robust composite structure, the as-prepared Fe2O3@N/Cl–C anode material delivers competent lithium-ion storage properties, including high reversible capacity of 1010 mAh g−1 (based on the mass of the as-prepared nanocomposite) at 0.1 A g−1, decent rate performance upon a rigorous current change, and superior cycling stability with 955 mAh g−1 after 180 cycles as well as a sustained Coulombic efficiency of about 99%. This structural design may provide a new avenue for achieving efficient iron oxide-based materials in chemical and electrochemical applications such as catalysis, lithium-ion batteries, and sodium-ion batteries.

The [Rh(L-alaninate)(cod)] (cod = 1,5-Cyclooctadiene) complex was synthesized and characterized. Asymmetric polymerizations of achiral phenylacetylene with two hydroxyl groups and a dodecyl group (DoDHPA) were performed by using the rhodium complex as the catalyst to provide polymers with a higher molecular weight (&gt, 105) than the polymers obtained using the [Rh(cod)Cl]2 initiator systems. The resulting polymers showed circular dichroism (CD) signals at approximately 310 and 470 nm, indicating that they have a preferential one-handed helical structure. The helix sense in the polymer main chain was controlled by the sign of the catalyst chirality. These findings suggest that the rhodium complex with a chiral amine is the true active species for the helix-sense-selective polymerization of DoDHPA. The [Rh(L-alaninate)(cod)] complex also exhibits high catalytic activity in the polymerization of phenylacetylene (PA) to give a high yield and molecular weight. All these results demonstrate that this Rh complex is an excellent catalyst for the polymerization of phenylacetylene monomers.

Citrate is commonly used as an anticoagulant in hemodialysis for chronic renal failure (CRF) and for the regulation of the immune dysfunction in CRF patients. The objective of this study was to investigate the effect of citrate on the balance of T helper 17 (Th17) and regulatory T (Treg) cells in CRF. The levels of blood urea nitrogen (BUN) and serum creatinine (Scr) were significantly increased in the CRF model group compared to the control group, and were decreased in the citrate-treated groups. Citrate treatment inhibited the viability of Th17 cells while elevating the viability of Treg cells in CRF rats. Moreover, Th17-related cytokines significantly decreased while the Treg-related cytokines significantly increased with citrate treatment. Moreover, citrate had a negative influence on the deviation of Th17/Treg cells in CRF rats. Therefore, our study suggests that citrate had an anti-inflammatory effect on CRF through the modulation of the Th17/Treg balance.

The microstructure and hydrogen absorption/desorption properties of (40-x)Ti–40V–10Cr–10Mn-xSc (x = 0, 5, 10, 15) were investigated. The result shows that the Sc-free sample has a V-based solid solution phase with body-center cubic structure (BCC phase), while the Sc-contained samples consist of a BCC phase, a C14-type Laves phase, a Sc-based hydride phase with face-center cubic (FCC) structure (derived from hydrogen decrepitation process). The hydrogen absorption kinetic process can be described by chemical reaction mechanism when x = 0, 10, 15 and 3-D diffusion mechanism when x = 5. As the Sc content increases, the hydrogen absorption capacity at 298 K first decreases and then increases, getting the minimum when x = 5. However, the hydrogen desorption capacity and hysteresis at 298 K are gradually improved with Sc content increasing.

Spinel LiMnTiO4 as the cathode material for Li-ion batteries has been synthesized by a sol–gel method. The LiMnTiO4 cathode possesses two voltage plateaus, and exhibits an initial discharge capacity of 203.3 mAh g−1. After 47 charge–discharge cycles, the capacity retention of the LiMnTiO4 cathode is 77.5 %, which is much higher than that of LiMn2O4 (47.9 %). Ti substitution can successfully suppress the formation of tetragonal phase during cycling and hence increase the structural stability; however, it decreases the discharge capacity. Multi-walled carbon nanotubes (MWCNTs) were mechanically milled with the pristine LiMnTiO4. The as-prepared LiMnTiO4/MWCNTs composite electrode exhibits significantly improved electrochemical properties including rate capability and cycling stability, as compared with LiMnTiO4.

A novel phenylacetylene monomer having a perfluorinated alkyl group (M-F) was synthesized and polymerized in a chiral catalytic system to yield a one-handed helical polymer. The ability and efficiency of the chiral induction of the fluorine-containing monomer in the helix-sense-selective polymerization (HSSP) was much higher than those of a monomer having the corresponding alkyl group (M-H) we reported before. The resulting polymer showed cis-cisoidal one-handed helical conformation, and was suitable for highly selective photocyclic aromatization (SCAT) to give a 2D surface modifier (). Oxygen permselectivity through a base polymer membrane was highly enhanced from 1.83 to 2.36 by adding a small amount (1-5 wt%) of the 2D surface modifier . The improvement was thought to be caused by improvement of solution selectivity on the membrane surface which the 2D surface modifier effectively covered.

Although two-dimensional polymers (2DPs) and related materials are very attractive subjects for research because they are expected to function as ideal gas separation membrane materials, we need to...

Helix-sense-selective polymerisation of three new achiral substituted acetylenes containing two bulky π-conjugated planar substituents via imino groups by using catalytic amounts of a chiral source yielded soluble and statically stable one-handed helical polymers which were stabilized by intramolecular steric hindrance.

Na-substituted Li 2 MnSiO 4 nanoparticles as cathode materials for lithium ion batteries were successfully synthesized by sol–gel method. The structure, morphology and electrochemical properties showed that Li 2− x Na x MnSiO 4 ( x = 0.1 and 0.2) possessed smaller particle size, larger specific surface area and delivered higher discharge capacity compared to those of pristine Li 2 MnSiO 4 , especially at a Na substituted ratio of 0.1. In addition, Li 1.9 Na 0.1 MnSiO 4 /C nanocomposite coated with uniform carbon layer demonstrated significantly improved electrochemical performance in terms of discharge capacity. The experimental results revealed that ion substitution and carbon coating might be a feasible method to improve the electrochemical properties of this material.

Three novel phenylacetylenes having two hydroxyl groups via different kinds of spacers between the two hydroxyl groups and benzyl group were synthesized and polymerized. Two of the resulting polymers having oxyalkylene spacers between the hydroxyl group and benzyl group had good membrane forming ability, relatively high oxygen permselectivity and high oxygen permeability. By introducing the oxyalkylene spacers, the membrane forming abilities and oxygen permselectivity were enhanced. Oxygen permselectivity ( P O 2 / P N 2 = 2.67 ) of the polymer membrane having the longest spacers was higher than that (2.19) of polymer without any spacers. It may be because the columnar content and then defects decreased when the cis-cisoid conformation was changed to cis-transoid conformation. In addition, by decreasing the columnar content of the membrane from the polymer without any spacers, which could be controlled by conditions in membrane preparation, the membrane forming ability and oxygen permselectivity were effectively enhanced (from 2.19 to 2.61) without any drop of oxygen permeability.

Cation disordered Li 2 CoTiO 4 titanate with 3D lithium ion channels could be a promising new cathode material for lithium ion batteries due to its high theoretical capacity. Herein the Li 2 CoTiO 4 materials with tunable nanostructures were synthesized by a sol–gel method and subsequent heat treatment at different temperatures. The microstructure and electrochemical properties of the nanocrystalline Li 2 CoTiO 4 materials have been systematically investigated. The Li 2 CoTiO 4 material synthesized at lower temperature possessed smaller particle size and grain size, and allowed a higher reversible extraction of lithium ions per formula unit. Furthermore, the small particle size enabled insertion of lithium along short diffusion paths, and thus an increase of the lithium ion diffusion coefficient.

As a group of attractive photoelectromagnetic and catalytic functional materials, metal oxychlorides have been attracting attention for electrochemical energy storage in rechargeable chloride ion battery (CIB) systems recently. Their application, however, is limited by the complicated synthesis and/or poor cycling stability. Herein, a facile strategy using vacuum impregnation and subsequent thermal decomposition at mild conditions has been developed to synthesize the FeOCl/CMK-3 nanocomposite material. Benefiting from the nanoconfined structure, a high-performance FeOCl/CMK-3 cathode, which has a high discharge capacity of 202 mAh g–1, superior cycling stability, and significantly improved charge transfer and chloride ion diffusion, is achieved. The electrolyte component is found to show a high affinity with the chlorine layer in the FeOCl phase, inducing evident expansion of the FeOCl layers along the b-axis direction and thus boosting a new potential liquid exfoliation approach for preparing 2D FeOCl ma...

A brand new, soluble quadruple-stranded copolymer is synthesized by using a self-template polymer from a new monomer. In addition, another very unique quadruple-stranded copolymer having a π-π stacking supramolecular polymer main chain is synthesized by selective photocyclic aromatization of the quadruple-stranded copolymer. The two quadruple-stranded copolymers gave self-standing membranes.

Three chiral phenylacetylenes having an l -amino alcohol residue and two hydroxymethyl groups and an achiral phenylacetylene having two hydroxyl groups and a dodecyl group were copolymerized by using an achiral catalyst ((nbd)Rh + [η 6 -(C 6 H 5 )B − (C 6 H 5 ) 3 ]) (nbd = norbornadiene) to produce copolymers with M w of 0.5 × 10 4 –15.2 × 10 4 . The copolymers exhibited the Cotton effect at wavelengths assignable to the main chain, indicating that the copolymers adopted one-handed helical conformations. Self-supporting membranes of the resulting copolymers were prepared by the solution casting method. We measured the gas permeabilities (CO 2 /N 2 , CO 2 /CH 4 ) of the copolymer membranes. The separation selectivity factor of CO 2 /N 2 was 17.9, and the CO 2 permeability coefficient of CO 2 /N 2 was 77 Barrers.

A facile synthesis of novel five 2D (planar) surface modifiers having a triphenylbenzene derivatives as a 2D structure has been achieved by the highly selective photocyclic aromatization reaction. Efficient enhancement of oxygen permselectivities through the three polymer membranes has been achieved by adding a small amount ( P O 2 -α graph were over or close to the upper boundary line by Robeson in 1991. Since all the membranes containing the 2D surface modifiers showed better permselectivities than the corresponding substrate membranes, it is very promising for the future.

High capacity Li2MnSiO4/C nanocomposite with good rate performance was prepared via a facile sol-gel method using ascorbic acid as carbon source. It had a uniform distribution on particle size of approximately 20 nm and a thin outlayer of carbon. The galvanostatic charge-discharge measurement showed that the Li2MnSiO4/C electrode could deliver an initial discharge capacity of 257.1 mA h g−1(corresponding to 1.56 Li+) at a current density of 10 mA g−1at 30°C, while the Li2MnSiO4electrode possessed a low capacity of 25.6 mA h g−1. Structural amorphization resulting from excessive extraction of Li+during the first charge was the main reason for the drastic capacity fading. Controlling extraction of Li+could inhibit the amorphization of Li2MnSiO4/C during the delithiation, contributing to a reversible structural change and good cycling performance.

Two kinds of novel nanoporous polycondensates (sc(Rf)) have been synthesized by two new preparation methods consisting of polycondensation and highly selective photocyclicaromataization of 1/3 helical cis-cis polyphenylacetylenes with polymerizable groups. By the original methods, new well-defined sheet polymers having nanopores or nanospaces have been synthesized for the first time. Their composite membranes, containing small amounts (1.0 wt%) of sc(Rf), had ultrahigh oxygen permeability (Po2 &gt, 1000 barrer), and their plots were beyond the Robeson&rsquo, s upper bound line in the graph of oxygen permselectivity (&alpha, = Po2/PN2) versus Po2. Both &alpha, and Po2 values were enhanced by adding only small amounts (1.0 wt%) of sc(Rf). One of the sc(Rf)s synthesized on the base membrane surface showed the best performance, i.e., Po2 = 5300 barrer and &alpha, = 2.5. The membrane surface was effectively covered by sc(Rf), judging from the contact angle values. It is thought that nanopores and nanospaces created in and between sc(Rf) molecules played an important role for the enhancement of both &alpha, and Po2/PN2.

A novel achiral phenylacetylene having a bulky t-butyl group was synthesized and polymerized by a chiral catalytic system containing [Rh(nbd)Cl]2 (nbd: norbornadiene) and chiral amines to yield a o...