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The reasonable design of the precursor of the carbon-based nanocatalyst is an important pathway to improve its catalytic performance. In this study, a simple solvothermal method was used to synthesize [Cu(TPT)(2,5-tdc)]·2H 2 O ( Cu-MOF ) containing N and S atoms in one step. Further in-situ carbonization of the Cu-MOF as the precursor was used to synthesize Cu/Cu x S embedded N,S-doped porous carbon (Cu/Cu x S/NSC) composites. The catalytic activities of the prepared Cu/Cu x S/NSC were investigated through catalytic reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP). The results show that the designed Cu/Cu x S/NSC has exceptional catalytic activity and recycle stability, showing the reaction rate constant is 0.0256 s -1 , and the conversion rate still exceeds 90% after 15 cycles. Meanwhile, the efficient catalytic reduction of dyes (CR, MO, MB and RhB) confirmed its versatility. Finally, the active sites of the Cu/Cu x S/NSC catalysts were analyzed and a possible multi-component synergistic catalytic mechanism was proposed.

The controlled syntheses of glycerol-based polymers, involving poly(glycidol) (PG)-backbones and thermoresponsive oligo(oxyethylene)-side chains, are described. The organocatalytic ring-opening polymerizations of benzyl glycidyl ether (BnGE) were performed to produce poly(benzyl glycidyl ether)s (PBnGEns) in which the degree of polymerization (n) was predetermined, followed by the removal of the inherent protection groups. For these polymerization/deprotection stages, the synthesis of two major types of polymers is emphasized, in which one is “pristine” PG without any specific end-groups (PGn) and the other is the α-end functionalized PG with hydrophobic aliphatic and aromatic groups (R-PGn). The post-modification reactions based on the addition reactions of isocyanate derivatives to the hydroxyl side groups were adopted for PGn and R-PGn, thus producing poly[glycidyl oligo(oxyethylene)carbamate]s with diverse structures. The structures can generally be expressed as PGn-EOmR′ and R-PGn-EOmR′, where (i) the degree of polymerization (n), (ii) the alkyl group at the periphery of the side groups (R′), (iii) the number of oxyethylene chains (m), and (iv) the α-end group (R) can be independently controlled and/or selected. The effects of the parameters/structures (i)–(iv) on the thermoresponsive properties and the supporting data for the phase transitions in aqueous media are described in detail.

A synthetic method for a series of poly(glycidol) (PG)-based amphiphilic block copolymers is presented with an emphasis on the catalyst switch method from an organic superbase (t-Bu-P4) to another with reduced basicity (t-Bu-P2) during sequential ring-opening polymerization (ROP). This methodology allowed the first ROP of an epoxide monomer and the second ROP of cyclic ester monomers or a cyclic carbonate monomer to occur in a controlled manner, producing diblock copolymers with well-defined structures. Deprotection of the polyether segment resulted in amphiphilic block copolymers with PG as the effective hydrophilic segment and three different aliphatic polyesters or polycarbonate as the hydrophobic segments. The block copolymers’ physicochemical properties were systematically examined, demonstrating their excellent micelle-forming properties in aqueous media.

The reasonable design of the precursor of a carbon-based nanocatalyst is an important pathway to improve catalytic performance. In this study, a simple solvothermal method was used to synthesize [Cu(TPT)(2,5-tdc)] ⋅ 2H

Toluene was selected as a representative VOCs due to the toxicity and difficulty to degrade aromatic hydrocarbons. The degradation of toluene by the DBD plasma-catalytic method paid much attention. In this process, Mn-based catalysts with Ce, Co were recommendable. However, Mn-based composite catalyst to deal with toluene with DBD plasma-catalytic method, the by-product formation, optimal composition and service life are still not clear. In this work, MnxCoyCezOn catalysts were prepared by the hydrothermal method. The physicochemical characteristics of the catalysts were analyzed. The removal efficiency and by-product analysis of toluene by the DBD plasma-catalytic method with MnxCoyCezOn catalysts were investigated. It was found that MnxCoyCezOn has a good crystalline phase composition, high amounts of chemisorbed and lattice oxygen. The combination of Mn and Co would significantly increase the lattice oxygen of the catalyst, and the addition of Ce can increase the content of chemisorbed oxygen. Through evaluation of catalytic activity, the catalyst of Mn₁Co₁ showed the best catalytic performance. After the continuous test, the Mn₁Co₁ catalyst showed the highest carbon balance and the lowest NOₓ generation rate when the continuous reaction time was less than 5 h.

In this paper, we describe a comprehensive study of the thermoresponsive properties of statistic copolymers and multiblock copolymers synthesized by poly(glycidol)s (PG) and poly(ethyl glycidyl ether) (PEGE) with different copolymerization methods. These copolymers were first synthesized by ring-opening polymerization (ROP), which was initiated by tert-butylbenzyl alcohol (tBBA) and 1-tert-butyl-4,4,4-tris(dimethylamino)-2,2-bis[tris(dimethylamino)phosphoranylidenamino]-2Λ5,4Λ5-catenadi(phosphazene) (t-Bu-P4) as the catalyst, and then the inherent protective groups were removed to obtain the copolymers without any specific chain end groups. The thermoresponsive property of the statistic copolymer PGx-stat-PEGEy was compared with the diblock copolymer PGx-b-PEGEy, and the triblock copolymers were compared with the pentablock copolymers. Among them, PG-stat-PEGE, PG-b-PEGE-b-PG-b-PEGE-b-PG, and PEGE-b-PG-b-PEGE-b-PG-b-PEGE, and even the specific ratio of PEGE-b-PG-b-PEGE, exhibited LCST-type phase transitions in water, which were characterized by cloud point (Tcp). Although the ratio of x to y affected the value of the Tcp of PGx-stat-PEGEy, we found that the disorder of the copolymer has a decisive effect on the phase-transition behavior. The phase-transition behaviors of PG-b-PEGE, part of PEGE-b-PG-b-PEGE, and PG-b-PEGE-b-PG copolymers in water present a two-stage phase transition, that is, firstly LCST-type and then the upper critical solution temperature (UCST)-like phase transition. In addition, we have extended the research on the thermoresponsive properties of EGE homopolymers without specific α-chain ends.

A growing body of evidence suggested that time can be represented separately either on the lateral, sagittal or vertical axis. However, it is still not clear whether these mental time lines from different origins could co-exist, or compete with each other such that if one is selected, the others are inhibited? The present study addressed this question using a multi-dimensional free-choice paradigm with Mandarin speakers in three experiments. The results showed that significant spatial-temporal congruency effects were found both on the lateral and sagittal/vertical axes in the horizontal/coronal plane either in a temporal judgment relevant or irrelevant task. By contrast, the spatial-temporal congruency effects did not appear at the same time on the sagittal and vertical axes in the sagittal plane. These results supported that lateral mental time line could co-exist with the other two, while sagittal and vertical mental time lines could not co-exist with each other. This finding implied that the space-time mapping mechanism is different between the lateral axis and the sagittal and vertical axes, whereas it is the same for the latter two axes.

The interlamellar spacing of layered double hydroxides (LDHs) was enlarged by dodecyl sulfonate ions firstly, and then, (3-aminopropyl)triethoxysilane (APS) was chemically grafted (APS/LDHs). The structural characteristics and thermal stability of these prepared samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), reflectance Fourier transform infrared spectrometer (FTIR), thermogravimetric analysis (TG), and elemental analysis (EA) respectively. The CO2 adsorption performance was investigated adopting TG and diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). The results presented that the CO2 adsorption capacity on APS/LDHs was as high as 90 mg/g and showed no obvious reduction during a five cyclic adsorption-desorption test, indicating its superior performance stability. The DRIFTS results showed that both carbamates and weakly bounded CO2 species were generated on APS/LDHs. The weakly adsorbed species was due to the different local chemical environment for CO2 capture provided by the surface moieties of LDHs like free silanol and hydrogen bonds.

The interlamellar spacing of layered double hydroxides (LDHs) was enlarged by dodecyl sulfonate ions firstly, and then, (3-aminopropyl)triethoxysilane (APS) was chemically grafted (APS/LDHs). The structural characteristics and thermal stability of these prepared samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), reflectance Fourier transform infrared spectrometer (FTIR), thermogravimetric analysis (TG), and elemental analysis (EA) respectively. The CO2 adsorption performance was investigated adopting TG and diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). The results presented that the CO2 adsorption capacity on APS/LDHs was as high as 90 mg/g and showed no obvious reduction during a five cyclic adsorption-desorption test, indicating its superior performance stability. The DRIFTS results showed that both carbamates and weakly bounded CO2 species were generated on APS/LDHs. The weakly adsorbed species was due to the different local chemical environment for CO2 capture provided by the surface moieties of LDHs like free silanol and hydrogen bonds.

A class of polysubstituted functionalized furans was synthesized efficiently starting from readily available furans involving the oxidative ring opening of the furan rings using NBS as an oxidant. The reaction proceeded through a sequence of oxidative dearomatization of the furan ring/spirocyclization/aromatization.

Background and Objectives Methylenetetrahydrofolate reductase (MTHFR) polymorphism may be a risk factor for male infertility. However, the epidemiologic studies showed inconsistent results regarding MTHFR polymorphism and the risk of male infertility. Therefore, we performed a meta-analysis of published case-control studies to re-examine the controversy. Methods Electronic searches of PubMed, EMBASE, Google Scholar and China National Knowledge Infrastructure (CNKI) were conducted to select eligible literatures for this meta-analysis (updated to June 19, 2014). According to our inclusion criteria and the Newcastle-Ottawa Scale (NOS), only high quality studies that observed the association between MTHFR polymorphism and male infertility risk were included. Crude odds ratio (OR) with 95% confidence interval (CI) was used to assess the strength of association between the MTHFR polymorphism and male infertility risk. Results Twenty-six studies involving 5,575 cases and 5,447 controls were recruited. Overall, MTHFR 677C>T polymorphism showed significant associations with male infertility risk in both fixed effects (CT+TT vs. CC: OR = 1.34, 95% CI: 1.23–1.46) and random effects models (CT+TT vs. CC: OR = 1.39, 95% CI: 1.19–1.62). Further, when stratified by ethnicity, sperm concentration and control sources, the similar results were observed in Asians, Caucasians, Azoo or OAT subgroup and both in population-based and hospital-based controls. Nevertheless, no significant association was only observed in oligo subgroup. Conclusions Our results indicated that the MTHFR polymorphism is associated with an increased risk of male infertility. Further well-designed analytical studies are necessary to confirm our conclusions and evaluate gene-environment interactions with male infertility risk.

The reaction proceeds through NBS-mediated oxidative dearomatization of the furan ring followed by spirocyclization and aromatization.

A velocity-adaptive channel estimation method using a lowpass filter is proposed. The bandwidth of the filter is determined by searching the spectrum autocorrelation results for the second highest peak location. The components which are higher than the maximum Doppler frequency are forced to zeros because they are just from noise if there is no spectrum leakage, which is in fact not the real case due to the truncation in the time domain. Therefore, a compensation for the removed leaking signal is made after zero forcing (ZF). Computer simulation shows that, in a wide range of mobile speed, the performance of the proposed estimation method in terms of the mean square error (MSE), is close to that of the ideal case in which Doppler frequency is perfectly known, and the compensation for the leaking signals improves the accuracy of channel estimation.

The bioactivity of Myoporum bontioides extracts to Plutella xylostella was studied with IIPC as evaluated index. The results showed that petroleum ether and chloroform extracts had a higher activity than ethyl acetate and alcohol extracts. At 0.01 gDW x ml(-1), the ODR of petroleum ether and chloroform extracts was 84.69% and 79.90%, and 76.47% and 45.70% after treated 1d and 3d, while the IIPC was 0.1565 and 0.2055, respectively. Provided with a higher concentration of 0.05 gDW x ml(-1), the ODR was 88.52% and 72.25%, and 87.33%, 58.37%, while the IIPC was 0.1125 and 0.2620, respectively. From the chloroform extract of Myopdrum Bontioides, three flavonoids, 2, 3-dihydro-5, 7-dihydroxy-2-phenyl-4H-1-Benzopyran-4-one (I), 3, 5, 7-trihydroxy-2-phenyl-4H-1-Benzopyran-4-one (II) and 5, 7-dihydroxy-3-methoxy-2-(4-methoxyphenyl)-4H-1-Benzopyran-4-one (III), were isolated, and their structure were identified based on the analyses of physical and spectrum data. Among these compounds, (II) had a better bioactivity to Plutella xylostella.

This study showed that the volatile oils from Myoporum bontioides had a significant repellent action on Plutella xylostella. When Plutella xylostella adults entered into the 4-arm selective olfactometer, the preferred times and average staying duration, in the order from more to less, were 3, 1, 4, and 2 arms, which showed a tendency of keeping away from the treatment arms. The males were more sensitive to the volatile oils than the females, when the velocity of flow was 200 ml.min-1. On the first day of the 3rd bioassay, the oviposition deterrent rate and IIPC of the volatile oils on Plutella xylostella adults was 94.48% and 0.0552, respectively. A liquid component of the volatile oils from Myoporum bontioides was isolated, purified, and identified as myoporone.