Metal‐Free Reaction of ortho‐Carbonylated Alkynyl‐Substituted Arylaldehydes with Common Amines: Selective Access to Functionalized Isoindolinone and Indenamine Derivatives

Herein we describe a reaction of ortho‐carbonylated alkynyl‐substituted arylaldehydes with common primary amines that can provide functionalized isoindolinone and 3‐hydroxylindenamine products in high yields. Depending on the substituent size of primary amines, two distinct reaction pathways were exploited selectively, that are, an initial aza‐conjugate addition followed by hydrogen transfer to access isoindolinone framework and a unique oxa‐conjugate addition followed by Petasis–Ferrier rearrangement to afford indenamine derivatives. In the presence of Et₃N, the reaction property of small primary amines was changed, proceeding to afford 3‐hydroxylindenamine derivatives efficiently. These products contain interesting substructures that exist in many natural products and bioactive molecules. The reaction features contain the use of transition‐metal‐free catalysts, simple operation, broad substrate scope, and product diversity.     

Establishment and validation of an SIL-IS LC–MS/MS method for the determination of ibuprofen in human plasma and its pharmacokinetic study

In this work, we developed and validated a highly sensitive, rapid and stable LC–MS/MS method for the determination of ibuprofen in human plasma with ibuprofen-d3 as a stable isotopically labeled internal standard (SIL-IS). Human plasma samples were prepared by one-step protein precipitation. The chromatographic separation was achieved on a Poroshell 120 EC-C₁₈ (2.1 × 50 mm, 2.7 μm). Aqueous solution (containing 0.05% acetic acid and 5 mm NH₄Ac) and methanol were selected as the mobile phase with gradient elution. An electrospray ionization source was applied and operated in negative ion mode. Multiple reaction monitoring mode was used for quantification using target fragment ions m/z 205.0 → 161.1 for ibuprofen and m/z 208.0 → 164.0 for SIL-IS, respectively. This method exhibited a linear range of 0.05–36 μg/ml for ibuprofen with correlation coefficient >0.99. Mean recoveries of ibuprofen in human plasma ranged from 78.4 to 80.9%. The RSD of intra- and inter-day precision were both < 5%. The accuracy was between 88.2 and 103.67%. The matrix effect was negligible in human plasma, including lipidemia and hemolytic plasma. A simple, efficient and accurate LC–MS/MS method was successfully established and applied to a pharmacokinetic study in healthy Chinese volunteers after a single oral administration of ibuprofen granules.     

Sandwich-like Catalyst–Carbon–Catalyst Trilayer Structure as a Compact 2D Host for Highly Stable Lithium–Sulfur Batteries

Herein, we propose the construction of a sandwich-structured host filled with continuous 2D catalysis–conduction interfaces. This MoN-C-MoN trilayer architecture causes the strong conformal adsorption of S/Li₂S_x and its high-efficiency conversion on the two-sided nitride polar surfaces, which are supplied with high-flux electron transfer from the buried carbon interlayer. The 3D self-assembly of these 2D sandwich structures further reinforces the interconnection of conductive and catalytic networks. The maximized exposure of adsorptive/catalytic planes endows the MoN-C@S electrode with excellent cycling stability and high rate performance even under high S loading and low host surface area. The high conductivity of this trilayer texture does not compromise the capacity retention after the S content is increased. Such a job-synergistic mode between catalytic and conductive functions guarantees the homogeneous deposition of S/Li₂S_x, and avoids thick and devitalized accumulation (electrode passivation) even after high-rate and long-term cycling.     

Effectively promoted catalytic activity by adjusting calcination temperature of Ce-Fe-Ox catalyst for NH3-SCR

A series of Ce-Fe-O_x catalysts prepared by the different calcination temperatures (marked as CF-X, where X represented calcination temperature) were used to the selectivity catalytic reduction of NO_x by NH₃. The results explained the relationship between calcination temperature and the sulfate species over Ce-Fe-O_x, and then investigated the surface acidity and catalytic performance. The large amounts of sulfate species were formed over CF-450 and CF-550 while it was decomposed with further the increasing of calcination temperature, which resulted in the loss of surface acidity, causing a decrease in the catalytic activity over Ce-Fe-O_x. Thereby, the CF-450 catalyst showed the best catalytic activity and over 90% NO_x conversion was obtained at 244–450 °C. Besides, the favored pore structure, more Fe³⁺ active species, higher Ce³⁺ concentration and the abundance of chemical adsorbed oxygen species, as well as the surface acid sites, would together contribute to the excellent catalytic activity of CF-450 catalyst.     

聚(碳酸丁二醇酯-co-三环癸烷二甲醇碳酸酯)的制备与性能

采用熔融酯交换和缩聚两步法,合成了以1,4-丁二醇、4,8-三环[5.2.1.0(2,6)]癸烷二甲醇和碳酸二苯酯为原料的聚(碳酸丁二醇酯-co-三环癸烷二甲醇碳酸酯)(PBTCx, x为进料中TCD占二元醇总量的百分比)。用1H NMR和13C NMR对PBTCs的微观结构和组成进行了表征。采用GPC、 DSC、 XRD、 TG对PBTCs的分子量、玻璃化转变温度(Tg)、热稳定性等进行了研究。结果表明,PBTCs的Mw为10500~124800 g?mol-1, Mn为6300~73000 g?mol-1, PDI为1.59~1.73; PBTCs呈无定形态、Tg为-3.43 ℃~70.90 ℃, PBTCs表现出比PBC更高的热稳定性。薄膜拉伸试验结果表明,PBTC30(拉伸强度为33.54 MPa,断裂伸长率为275.69%)和PBTC40(拉伸强度为32.13 MPa,断裂伸长率为294.63%)具有较高的强度和韧性,在薄膜材料中具有一定的应用潜力。     

Significant Acceleration of Photocatalytic CO2 Reduction at the Gas-Liquid Interface of Microdroplets**

Solar-driven CO₂ reduction reaction (CO₂RR) is largely constrained by the sluggish mass transfer and fast combination of photogenerated charge carriers. Herein, we find that the photocatalytic CO₂RR efficiency at the abundant gas-liquid interface provided by microdroplets is two orders of magnitude higher than that of the corresponding bulk phase reaction. Even in the absence of sacrificial agents, the production rates of HCOOH over WO₃ ⋅ 0.33H₂O mediated by microdroplets reaches 2536 μmol h⁻¹ g⁻¹ (vs. 13 μmol h⁻¹ g⁻¹ in bulk phase), which is significantly superior to the previously reported photocatalytic CO₂RR in bulk phase reaction condition. Beyond the efficient delivery of CO₂ to photocatalyst surfaces within microdroplets, we reveal that the strong electric field at the gas-liquid interface of microdroplets essentially promotes the separation of photogenerated electron-hole pairs. This study provides a deep understanding of ultrafast reaction kinetics promoted by the gas-liquid interface of microdroplets and a novel way of addressing the low efficiency of photocatalytic CO₂ reduction to fuel.     

A cost-effective anionic flocculant prepared by grafting carboxymethyl cellulose and lignosulfonate with acrylamide

How to efficiently utilize most abundant biomass of cellulose, lignin and their derivatives has become an emerging challenge as the anticipative oil depletion. In this paper, the ternary anionic copolymer of carboxymethyl cellulose-acrylamide-lignosulfonate (CAL) was successfully prepared by hydrothermal polymerization. Based on the flocculation characteristics of cationic methylene blue, the optimal polymerization process was confirmed as the raw material ratio of 1:1:1, initiator dosage of 0.9 wt %, the reaction time was 5 h and the reaction temperature was 55 °C. The results showed that the decolorization ratio was 87.5% at the CAL dosage of 600 mg/L for the 500 mg/L methylene blue simulated wastewater. The CAL achieved fast flocculation kinetics and super color removal ratios in the wide ranges of environmental pH, temperature and salt concentration. The flocculation mechanism is single charge neutralization. Moreover, the estimated treatment cost of CAL is 68.3% lower than that of commercial anionic PAM. The prepared anionic CAL flocculant has the characteristics of environmental safety, excellent flocculation performance and cost-effectiveness, which shows great potential in the field of dye wastewater treatment, and also provides a feasible way for the effective utilization of biomass resources.

     

Metal-Chelate Affinity Precipitation with Thermo-Responsive Polymer for Purification of <Emphasis Type="Italic">ε</Emphasis>-Poly-<Emphasis Type="SmallCaps">l</Emphasis>-Lysine

ε-Poly-l-lysine (ε-PL) is a natural preservative for food processing industry. A thermo-responsive polymer, attached with Cu²⁺ or Ni²⁺, was prepared for metal-chelate affinity precipitation for purification of ε-PL. The low critical solution temperatures (LCSTs) of these polymers were close to the room temperature (31.0–35.0 °C). The optimal adsorption conditions were as follows: pH 4.0, 0 mol/L NaCl, ligand density 75.00 μmol/g, and 120 min. The ligand Cu²⁺ showed a stronger affinity interaction with ε-PL and the highest adsorption amount reached 251.93 mg/g polymer. The elution recovery of ε-PL could be 98.42% with 0.50 mol/L imidazole (pH = 8.0) as the eluent. The method could purify ε-PL from fermentation broth and the final product was proved as electrophoretic pure by SDS-PAGE. Moreover, these affinity polymers could be recycled after the purification of ε-PL and the recoveries were above 95.00%.

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Graphical Abstract Scheme for affinity precipitation of ε-PL

     

THE COMPACT COMPOSITION OPERATOR ON THE μ-BERGMAN SPACE IN THE UNIT BALL

nAbstract Let p 0 and μ be a normal function on [0, 1), ν(r) =(1-r~2)~(1+(n/p)) μ(r) for r ∈ [0, 1). In this article, the bounded or compact weighted composition operator T_φ,ψfrom the μ-Bergman space A~p(μ) to the normal weight Bloch type space β_ν in the unit ball is characterized. The briefly sufficient and necessary condition that the composition operator C_φis compact from A~p(μ) to β_ν is given. At the same time, the authors give the briefly sufficient and necessary condition that C_φis compact on β_μ for a 1.     

Bayesian variable selection with sparse and correlation priors for high-dimensional data analysis

The main challenge in working with gene expression microarrays is that the sample size is small compared to the large number of variables (genes). In many studies, the main focus is on finding a small subset of the genes, which are the most important ones for differentiating between different types of cancer, for simpler and cheaper diagnostic arrays. In this paper, a sparse Bayesian variable selection method in probit model is proposed for gene selection and classification. We assign a sparse prior for regression parameters and perform variable selection by indexing the covariates of the model with a binary vector. The correlation prior for the binary vector assigned in this paper is able to distinguish models with the same size. The performance of the proposed method is demonstrated with one simulated data and two well known real data sets, and the results show that our method is comparable with other existing methods in variable selection and classification.