响应面法优化石榴保健果醋发酵工艺及其降糖降脂活性

以川产药食资源石榴为主要原料,通过单因素试验及响应面法对石榴保健果醋的醋酸发酵工艺进行优化,并探讨其降糖降 脂活性。 结果表明,石榴保健果醋的醋酸发酵最佳条件：初始酒精度9%vol、醋酸菌接种量10%、发酵时间8 d、发酵温度29 ℃。 在此优 化发酵工艺条件下,发酵液总酸度最高可达4.732 g/100 mL,所得的石榴保健果醋颜色鲜红,果醋香气浓郁,风味俱佳;同时,药效试 验表明,石榴保健果醋能明显或部分降低小鼠血清空腹血糖（FBG）、总胆固醇（TC）和甘油三酯（TG）的含量,升高胰岛素敏感指数（ISI）,提高机体对胰岛素的敏感性,显示出较好的改善糖脂代谢作用。     

Photocatalytic overall water splitting by Z-scheme g-C3N4/BiFeO3 heterojunction

Solar water splitting by photocatalysis in the absence of sacrificial agent has been identified as a promising approach to produce green hydrogen. Increasing photocatalytic efficiency is the core issue in this process. Forming heterojunctions is one potential solution to improve photoactivity. Herein, we successfully synthesized several g-C₃N₄/BiFeO₃ composites containing different mass ratio of g-C₃N₄ by an uncomplicated and cost-effective method. The composite samples exhibited remarkably enhanced photocatalytic performance compared with the bare BiFeO₃ and g-C₃N₄. The highest hydrogen production rate obtained is ~ 160.75 μmol h⁻¹.g-¹ under UV irradiation and ~23.31 μmol h⁻¹.g-¹ under visible light irradiation. This enhanced photocatalytic activity is attributed to the synergistic effect of the junction and Z-scheme charge transfer mechanism between BiFeO₃ and g-C₃N₄, which can effectively accelerate the separation of photogenerated electron-hole pairs and also capability of carrying out redox reaction.     

Well-dispersed CoSx nanoparticles modified tubular sulfur doped carbon nitride for enhanced photocatalytic H2 production activity

Appropriate dispersion of cocatalyst on semiconductor for improving photocatalytic H₂ production efficiency is a challenging work in semiconductor photocatalysis. Herein, we constructed the noble-metal-free CoS_x modified tubular sulfur doped carbon nitride (SCN) photocatalysts by chemical precipitation process. The amorphous CoS_x well dispersed on SCN served as H₂ production sites, which reduced the overpotential and inhibited the recombination of photogenerated carriers by interfacial charge transfer. Maximized H₂ production rate of 573.06 μmol g⁻¹ h⁻¹ under visible light irradiation was obtained by optimizing the CoS_x loading proportion to 2.4%, which was higher than that of 0.75 wt% Pt/SCN. In addition, a possible mechanism for improved H₂ production activity was proposed based on the experiments and discussion. This work provides a new strategy to design rational structure of non-noble metal cocatalyst modified photocatalyst to further improve H₂ production performance.     

Generation of variational standard plant room solutions

We have used the object-based CAD programming to take advantage of standardisation to handle the selection, sizing, layout and (potentially) pipe routing for Low-Pressure Hot Water (LPHW) plant rooms in buildings. Our approach combines automation and interactivity. From a simple specification of the plant room geometry (an orthogonal polygon with known obstructions, openings and external walls), and the heating load in kW, our software proceeds through a number of steps. First, the number and size of standard modular boilers, pumps, etc., are determined from the heat load. Then, a compatible optimising 3D variational solution is generated, using Constraint Logic Programming. To do this, we firstly enumerate a satisfactory topological solution, and then refine it to form a compatible geometrical solution. The final step generates pipe routes, using optimisation techniques to minimise the length of pipes and the number of bends. The solution obtained can be modified or improved by the designer, for which we have interactivity. Modifying the topology of the solution or the geometry of the plant room is done directly through the graphic interface, e.g. modifying a boiler position is done by dragging; the system automatically updates the 3D model including the pipe routing while maintaining all the design rules. The solutions generated by our prototype have been tested against conventional solutions in a benchmarking exercise. Advantages have been underlined and suggestions for further development have been made.     

Nanocrystalline tin oxides and nickel oxide film anodes for Li-ion batteries

Tin oxides and nickel oxide thin film anodes have been fabricated for the first time by vacuum thermal evaporation of metallic tin or nickel, and subsequent thermal oxidation in air or oxygen ambient. X-ray diffraction (XRD) and scanning electron microscopy (SEM) measurements showed that the prepared films are of nanocrystalline structure with the average particle size <100 nm. The electrochemical properties of these film electrodes were examined by galvanostatic cycling measurements and cyclic voltammetry. The composition and electrochemical properties of SnO_x (1<x<2) films strongly depend on the oxidation temperature. The reversible capacities of SnO and SnO₂ films electrodes reached 825 and 760 mAh g⁻¹, respectively, at the current density of 10 μA cm⁻² between 0.10 and 1.30 V. The SnO_x film fabricated at an oxidation temperature of 600 °C exhibited better electrochemical performance than SnO or SnO₂ film electrode. Nanocrystalline NiO thin film prepared at a temperature of 600 °C can deliver a reversible capacity of 680 mAh g⁻¹ at 10 μA cm⁻² in the voltage range 0.01–3.0 V and good cyclability up to 100 cycles.     

Iron(II) phenanthroline-resin hybrid as a visible light-driven heterogeneous catalyst for green oxidative degradation of organic dye

A novel resin immobilized iron(II) phenanthroline [FePR] is prepared, characterized and exploited to understand C–C/C–O cleavage in Rhodamine B dye under visible light (λ ≥ 420 nm). Studies infer that both molecular oxygen and visible light are playing essential roles in photocatalysis, and pH is influencing the degradation. Photocatalysis by FePR involves oxo-iron ([Fe^IV(phen)₃ = O]) species as reactive intermediate. LC–MS studies on the aliquots of partially photodegraded RhB reveal benzoic acid as a main degradation product; however, complete degradation was achieved under optimum condition. Overall, the FePR is a stable heterogeneous photocatalyst, which can be used for advanced oxidative process in greener route.     

Charging d-Orbital Electron of ReS2+x Cocatalyst Enables Splendid Alkaline Photocatalytic H2 Evolution

Rhenium disulfide (ReS₂) holds expansive perspective in photocatalytic water-splitting field, but its H₂-production rate is severely impeded by the strong hydroxyl (OH_ad) adsorption on catalytic Re atoms. Herein, an ingenious strategy about charging d-orbital electrons of ReS_2+x cocatalyst by integrating metallic Au is explicitly clarified to effectively accelerate OH_ad desorption for promoting alkaline photocatalytic H₂-evolution activity. To this end, core-shell Au@ReS_2+x nanostructures as H₂-production cocatalysts are skillfully fabricated onto TiO₂ by a directional assembly pathway. Experimental and theoretical data validate an free-electron transfer from metallic Au core to S-rich ReS_2+x shell, thus essentially charging electrons to the d-orbital of Re atoms to construct active Re^(4-δ)+ sites. The charged d-orbital electron state of Re^(4-δ)+ atoms raises antibonding occupancy of the Re^(4-δ)+ OH_ad bonds, thereby accelerating OH_ad desorption and endowing core-shell Au@ReS_2+x cocatalysts an efficient H₂ production from alkaline water splitting. Moreover, the core-shell Au@ReS_2+x cocatalysts can effectively capture photogenerated electrons from TiO₂ as unveiled by operando Kelvin probe force microscopy. Consequently, the optimized TiO₂/Au@ReS_2+x photocatalyst achieves an exceptional H₂-production rate of 6013.45 µmol h⁻¹ g⁻¹ with releasing visual H₂ bubbles in alkaline media. This research furnishes original insights for charging orbital electrons to optimize the adsorption strength between intermediates and catalytic atoms.     

退火调控的3D交联TiNb2O7纳米棒电极用于高效柔性锂离子电容器（英文）

TiNb2O7的理论比容量高达280 mA h g^-1,是一类有前景的锂离子电容器负极材料.然而其较差的电子导电性严重限制了其倍率性能的提升.在本文中,我们在柔性碳布表面直接生长3D交联的TiNb2O7纳米棒多孔负极,并将其首次应用于柔性锂离子电容器;碳布的高导电性,单晶纳米棒结构较短的离子/电子传输路径以及良好的结构稳定性,有效提高了材料的倍率性能和循环稳定性.研究表明,Ti Nb2O7负极表现出优异的倍率性能(从1到40 C,容量保持率高达66.3%),出色的循环稳定性(>2000圈),以及良好的柔韧性(连续弯曲500次后容量无损失).此外,将无粘结剂的Ti Nb2O7负极和商用活性炭正极搭配成锂离子电容器,展现出了较高的质量和体积能量/功率密度(~100.6 W h kg^-1/4108.8 W kg^-1;10.7 m W h cm^-3/419.3 mW cm^-3),优于先前报道的混合超级电容器,同时该器件可以在180°弯曲状态下为LED灯供电.     

Robust nanoporous alumina monoliths by atomic layer deposition on low-density carbon-nanotube scaffolds

Synthesis of nanoporous alumina monoliths with controlled morphology and density is a challenge. Here, we demonstrate mechanically robust alumina monoliths synthesized by conformal overcoating of graphitic nanoligaments of low-density carbon-nanotube-based aerogels (CNT-CAs) by using atomic layer deposition. Young’s modulus of resultant monoliths increases superlinearly with the monolith density with an exponent of ∼2.4, defined by the morphology and connectivity of the CNT-CA scaffold. As a result, for a given monolith density, alumina-carbon composites have moduli comparable to those of CNT-CAs and significantly superior to those of pure alumina aerogels reported previously.