Listeria monocytogenes (LM) is one of the deadliest and most hazardous pathogens, posing extremely serious harm to the human health, hence developing simple and effective method for its highly sensitive detection is very important. In this work, by preparing Pt nanoparticles/hollow carbon spheres (Pt/HCNs) nanohybrid as nano-zyme, a simple and highly sensitive nanozyme-based electrochemical sensor was developed for the first time to detect LM based on aptamer (Apt)-regulated Pt/HCNs nanozyme activity. The as-prepared Pt/HCNs nanozyme can catalyze the oxidation of o-phenylenediamine to generate electroactive 2,3-diaminophenazinc (DAP) which offers an obvious reduction peak current. However, once bound to LM-Apt to form Apt/Pt/HCNs, the related enzyme-like activity of Pt/HCNs is inhibited remarkably and the reduction current of DAP nearly disappear owing to the covering of the active sites. Interestingly, in the presence of LM, the nanozyme activity can be recovered through the specific recognition of Apt towards LM. After optimizing various conditions, the designed Apt-regulated nanozyme-based electrochemical sensor shows excellent sensing performances for LM. Meanwhile, the designed sensors exhibits superior selectivity, specificity, reproducibility, stability and real applications. This work offers a simple and novel strategy for the effective and highly sensitive determination of various pathogens via altering simply the specific Apt.

分析化学是食品药品与生物化工类专业的基础必修课程,学生受众多,是开展思政教育很好的载体.本文对分析化学课程思政进行了整体设计,围绕大国崛起、区域建设、科学发展等7个方面选取案例素材,与课程内容有机融合,以"精益求精之工匠精神、敬畏诚信之职业操守"作为课程思政建设目标,探索思政元素融入课堂教学的途径,形成两个详细的课程思政实施案例,为新时代高校课程思政教学的提质增效提供思路.

As one of the most hazardous and deadliest pathogens, Listeria monocytogenes (LM) posed various serious diseases to the human being, thus designing effective strategy for its detection is of great significance. In this work, by preparing Ti3C2Tx MXenes nanoribbon (Ti3C2TxR) as carrier and selecting thionine (Th) acted simultaneously as signal probe and functional monomer, a LM pathogen-imprinted polymers (PIP) integrated probe electrochemical sensor was design to monitor LM for the first time, that was carried out through the electropolymerization of Th on the Ti3C2TxR/GCE surface in the existence of LM. Upon eluting the templates from the LM imprinted cavities, the fabricated PIP/Ti3C2TxR/GCE sensor can rebound LM cells effectively. By recording the peak current of Th as the response signal, it can be weakened when LM cell was re-bound to the LM imprinted cavity on PIP/Ti3C2TxR/GCE, and the absolute values of peak current change increase with the increasement of LM concentrations. After optimizing three key parameters, a considerable low analytical limit (2 CFU mL−1) and wide linearity (10–108 CFU mL−1) for LM were achieved. In addition, the experiments demonstrated that the PIP/Ti3C2TxR sensor offers satisfactory selectivity, reproducibility and stability.

本文介绍了化学分析课程资源库建设的背景、意义、原则、目标以及该课程资源库可实现的功能.详细探讨了化学分析课程的建设思路和主要内容,分析了利用资源库采用混合式教学的效果,提出了课程资源库建设中存在的主要几个问题即团队管理问题、资源应用问题、资源更新和管理问题,并就这些问题提出了建议.

微电子焊料是电子产品组装过程中不可或缺的重要组成部分,它能够将器件的各部分有效地连接在一起.随着5G时代的到来,电子技术向着高功率、高密度和集成化的方向发展,对于大功率器件的封装如IGBT、MOS、大功率LED等,也相应地对焊接材料提出了更高的、更全面的可靠性需求.

Three kinds of biscitraconimide (BCI) monomers, 4,4 '-(diaminodiphenylsulfone) biscitraconimide (DDS-BCI), 1,2-(ethylenediamine) biscitraconimide (EDA-BCI) and m-(xylylenediamine) biscitraconimide (MXDA-BCI), were respectively prepared from the reaction of citraconic anhydride with three different diamines by reflux dehydration in glacial acetic acid. As-prepared products further reacted with 4,4 '-thiodibenzenethiol (TDBT) and 1,6-hexanedithiol (HDT) to synthesize a series of new transparent thermoplastic polythioetherimides (PTEI) films with excellent solubility, high refractive index and low birefringence. All PTEI films had the 5% weight loss temperature between 332 degrees C and 417 degrees C and the thermal expansion coefficient ranged from 39.4-94.8 ppm/C, showing good thermal stability. Besides, the transmittance of PTEI film at 450 nm exceeded 85 %, the average refractive index (n(av)) measured at 589 nm reached up to 1.6236 similar to 1.6635 and in-plane/out of-plane birefringence (Delta n) values were between 0.0014 and 0.0036. Especially DDS-BCI/TDBT sample exhibited the highest refractive index, relatively small birefringence and excellent thermal stability among all PTEI films, which is expected to be an ideal advanced optical material.

用聚乙二醇、甲苯?2,4?二异氰酸酯及丙烯酸羟乙酯合成半封端聚氨酯丙烯酸酯,再以它对环氧丙烯酸酯进行改性,然后与光引发剂配制成阴极电泳涂料.考察了不同分子量的聚乙二醇对固化膜性能的影响.结果表明,电泳后光固化膜的玻璃化温度最高达58°C,附着力1级,柔韧性小于2 mm,耐冲击性(1 kg)大于40 cm,耐丙酮擦拭超过500次,光固化时间在12 s内,光泽优异.随着嵌入的聚乙二醇链段长度增加,水性树脂的黏度降低,固化膜的柔韧性增强,但光泽、耐丙酮擦拭性和铅笔硬度都降低.

A novel phosphorus/nitrogen-containing flame retardant (DOPO-AM) was synthesized by 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) and acrylamide (AM) and its chemical structure was characterized. DOPO-AM was added into diglycidyl ether of bisphenol-A (DGEBA) with curing agent m-xylylenediamine (MXDA)to prepare flame retarded epoxy resin to reduce the possibility of fire. The compounds with different valences sulfur respectively replace partial DGEBA resin to study the effects of sulfur valences on the flame retardance of epoxy resins. The results indicated that DOPO-AM had excellent flame retardance for epoxy resin. When phosphorus content was only 0.75%, DGEBS resin containing DOPO-AM achieved the limiting oxygen index value of 34.55% and vertical burning test (UL-94) V-0 rating. Although sulfur element is help for refractive index of epoxy resin, sulfur element in three kinds of valences all weaken the flame retardant of epoxy resin. Improving phosphorus content is help for the synergistic effect of P-N and P-N-S. Moreover, the flame retardance is not proportional to sulfur valence, sulfide with +2 valence had the best flame retardance. However, +6 valence sulfonic with strong oxidation effect worsen the flame retardant. Simultaneous thermal analysis of thermogravimetric analyzer and differential scanning calorimeter and scanning electronic microscopy photographs verified the above conclusion.

为提高米香型白酒的品质,将筛选得到的克鲁维毕赤酵母(Pichia kudriazevii)、异常维克汉逊酵母(Wickerha-momyces anomalus)、扣囊复膜酵母(Saccharomycopsis fibuligera)3株产香酵母与1株酿酒酵母(Saccharomyces cerevisiae)作为供试菌株,研究了其菌株形态、生长周期、抗逆性以及发酵特性,并探索了菌株间的相互作用对菌体生长与代谢的影响规律.结果显示,各菌株进入稳定期的时间存在明显差异.在抗逆性方面,4株菌均表现出良好的耐热性、耐酸性、乙醇耐受性与糖耐受性.产酸、产酯、产乙醇能力最强的菌株分别是S.fibuligera、P.kudriazevii、S.cerevisiae.相互作用方面,S.cerevisiae会抑制其余3株产香酵母的生长(P<0.05),而产香酵母对S.cerevisiae的生长无明显影响;此外,P.kudriazevii会显著抑制W.anomalus(P<0.05).4株菌最优的接种比例为106:106:106:106 CFU/mL,在接种3株产香酵母8 h后再接种S.cerevisiae,风味物质的含量最优.研究结果表明,供试菌株具备生物增香、提高酒体品质的良好潜力.

To enhance the comprehensive performance of lithium-ion batteries (LIBs), a novel fluorinated poly(aryl ether ketone) (FPAEK) compound was synthesized and further fabricated as a nonwoven fibrous separator for LIBs via an electrospinning method.

The thermostability and wettability of a separator play key roles in improving the safety and electrochemical properties of lithium-ion batteries (LIBs).

Adsorption and separation of ethane and ethylene has been studied on a robust Ca-based microporous metal–organic framework which shows ethane-selective adsorption over ethylene.

Two new copper bromide based coordination compounds 0D-Cu2Br2(3,5-dimethyl-pyridine)4 (1) and 1D-Cu2Br2(5-bromo-pyrimidine)2 (2) have been synthesized and structurally characterized. X-ray diffraction analyses reveal that the inorganic module of both compounds is Cu2Br2 rhomboid dimer coordinated by the organic ligands. Compound 1 is a zero-dimensional (0D) molecular complex while compound 2 is one-dimensional (1D) extended structure. Photoluminescence measurement results show that 1 emits green photoluminescence peaked at 520 nm, with an IQY of 82.4%. Compound 2 emits red photoluminescence peaked at 630 nm, with an IQY of 2.1%. Both compounds exhibit potential as rare-earth metal free lighting phosphor alternatives.

In this work, a cationic waterborne epoxy acrylic resin (WCEA) was synthesized from bisphenol an epoxy resin, acrylic acid, acrylic acid, hydroquinone as an inhibitor, and N, N-dimethylbenzylamine (DMBA) as a catalyst. The changes of NCO groups and acid value during the synthesis process were measured by chemical titration method, and its Fourier Transform Infrared (FTIR) spectra were investigated. The results indicate that the acidified waterborne resin has great water solubility and storage stability after grafting the half-blocked isocyanate.

Single crystals of a zero-dimensional (0 D) copper (I) complex 0 D-CuBr(3-picoline)(3) (1) has prepared at room temperature. Each molecule of 1 contains one copper ion, which coordinates to three organic ligands and one Br anion. The strong metal-to-ligand charge transfer (MLCT) along with the halide-to-metal charge transfer (XLCT) makes 1 an extremely strong green emitter with near-unity quantum efficiency, exhibiting potential application as lighting materials. Single crystals of a new zero-dimensional (0D) copper (I) complex 0D-CuBr(3-picoline)(3) has prepared at room temperature. It serves as an extremely strong green-yellow emitter with near unity quantum efficiency, exhibiting potential application as lighting materials.

A phosphorous-doped graphite felt (PGF) is fabricated and examined as electrode for vanadium flow battery (VFB). P doping improves the electrolyte wettability of GF and induces more defect sites on its surface, resulting in significantly enhanced activity and reversibility towards VO2+/VO2+ and V2+/V3+ couples. VFB with PGF electrode demonstrates outstanding performance such as high-rate capability under 50-400 mA cm(-2), wide-temperature tolerance at -20 degrees C-60 degrees C, and excellent durability over 1000 charge-discharge cycles. These merits enable PGF a promising electrode for the next-generation VFB, which can operate at high-power and all-climate conditions. (C) 2018 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights reserved.

In this study, halogen-free flame retardant tri(acryloyloxyethyl) phosphate (TAEP) was prepared using 2-hydroxyethyl acrylate and phosphorus oxychloride. The chemical structure of TAEP was characterized by Fourier transform infrared and proton nuclear magnetic resonance spectrometers. The mixture of TAEP, acrylamide, and pentaerythritol tetrathioglycolate with different P, N, and S content were used to prepare flame retarding optical resin via the click chemistry curing. The curing performance, thermal stability, and flame retardant performance of the optical resins were measured by differential scanning calorimeter, thermogravimetric analyzer, vertical burning tester, and limiting oxygen index test, respectively. Additionally, the morphology of the burned residual was investigated by scanning electronic microscopy, and the refractive indices of the optical resins were measured by an Abbe Refractometer. The results strongly indicated that increasing sulfur content in resins improved their refractive indices, but deteriorated their flame retardancy. Meanwhile, the nitrogen element was helpful for the flame retardancy of the optical resin. With S N, and P contents of 3.00%, 1.00%, and 6.70 wt %, respectively, the refractive index of the optical resin reached up to 1.4987, and its flame retardancy achieved the UL-94 V-0 level and the LOI value of 29.3%. (c) 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46648.

Halogen-free flame retardant tri(acryloyloxyethyl) phosphate (TAEP) optical resin was prepared using hydroxy ethyl acrylate (HEA) and phosphorus oxychloride and the chemical structure was characterized by Fourier transform infrared spectrometer and proton nuclear magnetic resonance spectrometer. Optical resins mixed by pentaerythritol tetrathioglycolic and TAEP with different S and P contents were obtained via click chemistry curing. The curing performance, thermal stability and flame retardant performance of the optical resins were analyzed by differential scanning calorimeter, thermogravimetric analyzer, and vertical burning tester, respectively. Additionally, the burned residual morphology of samples was investigated by scanning electronic microscopy, and the refractive indices of the optical resins were measured by an Abbe refractometer. The results revealed that increasing S content could improve the refractive indices of the resins; whereas, the flame retardant performances decreased. The optical resins with S content of 2% and P contents of 7.37% had refractive indices of 1.4935 and UL 94 V-0 flame retard level, respectively. The optical resins had good thermal stability and the 5% decomposition temperature reached up to 200.1 °C.

Carbon aerogel (CA)/α-Fe2O3@Polypyrrole (PPy) composites with double protective structure are synthesized via a solvothermal method with further in-situ polymerization of polypyrrole. The structure, morphology, loading content of α-Fe2O3 in composite and electrochemical properties are investigated by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, high resolution transmission electron microscopy, thermogravimetry, constant current charge/discharge tests, cyclic voltammetry tests and electrochemical impedance spectroscopy. The results show α-Fe2O3 directional grows on the inner carbon aerogel while embeds in the outer PPy layer. As an anode material of lithium ion batteries, the CA/α-Fe2O3@PPy composite electrode exhibits more excellent cycling stability and rate capability than that of the bare α-Fe2O3 and CA/α-Fe2O3. The unique structure is responsible for the excellent electrochemical performance, which not only provides double protection against the aggregation and volume changes of α-Fe2O3 particles, but also ensures favorable transport kinetics for both electron and lithium ion.

Developing low-cost and high selectivity membranes is critical for vanadium flow batteries (VFB) energy storage system. Among several potential candidates, sulfonated poly(ether ether ketone) (SPEEK) membrane is most promising, yet its proton conductivity and durability are still insufficient to meet the needs of practical applications. Here we report the preparation of a mussel-inspired polydopamine coated carbon nanotube embedded SPEEK mixed matrix membrane (S/CNT@PDA MMM) and its successful application in VFB. The acid-base interface interaction between the SPEEK matrix and the CNT@PDA filler is beneficial to construct additional proton transfer pathway as well as improve the mechanical property of the S/CNT@PDA MMM. Compared to pristine SPEEK membrane, the S/CNT@PDA MMM demonstrates higher proton conductivity, superior proton to vanadium ion selectivity and significantly enhanced stability. As a result, the VFB assembled with the S/CNT@PDA MMM exhibits greatly improved rate performance compared with the benchmark Nafion 115 membrane, and reaches the peak power density of 580 mW cm(-2) at 650 mA cm(-2). Moreover, the S/CNT@PDA MMM shows super long-term stability over 1000 cycles at 200 mA cm(-2), and wide temperature adaptability from - 20 degrees C to 50 degrees C, indicating the great potential of this MMM for practical application in VFB.