开菲尔粒及其发酵液中菌相分析

为了研制开菲尔发酵剂，本试验测定了开菲尔粒及其发酵液中几种主要微生物的数量。两者结果均表明其中乳酸菌多于醋酸菌，醋酸菌多于酵母菌，而且乳酸菌类中大多数为兼性厌氧菌。     

芝麻香型丢糟酒实验室生产模型的建立

该研究针对目前芝麻香型丢糟酒的生产过程设计相应的实验室模型并通过工厂实验予以佐证。采用高效液相色谱和改进Megazymes法检测样品中的残淀粉、含酒量等关键指标,并通过多重比较法评价模型的合理性和稳定性。结果表明,实验室模型-1能准确预测丢糟酒成熟酒醅的含酒量和残淀粉,为设计和优化针对芝麻香型丢糟酒的特种生物制剂提供快捷有效的预测手段;同时实验室模型-2也揭示了物料的均匀混合和酵母的活力对残葡萄糖、淀粉利用率和出酒率的显著影响。     

液相色谱法测定谷物中脱氧雪腐镰刀菌烯醇

建立检测谷物中脱氧雪腐镰刀菌烯醇(DON)的液相色谱方法,通过不同提取方法的比对来确定最佳的DON提取方案,并最终确定使用乙腈-水(体积比V/V,84/16)提取,经过DON专用净化柱的净化处理后,采用紫外检测器(λ=220 nm)及C18亲水分离柱测定。结果表明,用高速均质机均质4 min提取,可大幅度提高方法回收率,回收率达到90.7%~98.9%,方法最低检出限为50μg/kg。     

免疫磁珠高通量自动净化-超高效液相色谱法测定粮食中玉米赤霉烯酮

基于免疫磁珠高通量自动净化的前处理方法,使用超高效液相色谱仪对粮食中玉米赤霉烯酮的含量进行测定。首先将免疫磁珠与玉米赤霉烯酮的反应时间、样品提取液和不同粮食基质的净化效果进行优化。经方法验证,超高效液相色谱的检出限和定量限分别为3.5 μg/kg和12.0 μg/kg。在优化条件下,全麦粉和玉米全粉阴性样品的3 个添加水平的加标回收率在99.04%～109.26%之间,变异系数不大于6.88%。玉米全粉、全麦粉、糙米粉、小麦粉等粮食基质中玉米赤霉烯酮成分的国家有证标准物质或质控样品的测定结果在标准值及其扩展不确定度范围内,变异系数不大于3.54%,测定结果较为满意。采用Bland-Altman法对免疫磁珠净化法和免疫亲和柱净化法之间的差异进行分析,结果显示这2 种净化方法的差异在可接受范围内,因此,这2 种方法在净化和富集粮食中玉米赤霉烯酮时可互相代替使用。免疫磁珠净化方法配套使用的真菌毒素全自动净化仪可同时净化10～24 个样品,平均每个样品的净化时间约为2～3 min,实现粮食中玉米赤霉烯酮的高通量自动净化。超高效液相色谱分析速度快、灵敏度高、准确性高,可用于检测粮食中玉米赤霉烯酮的含量。     

海鲜面粒汤的研究

通过对海鲜面粒汤主要原料的选择 ,原料配比的研究 ,以及对结果进行品评分析 ,确定了该产品的最佳配方     

Multifunctional Artificial Artery from Direct 3D Printing with Built‐In Ferroelectricity and Tissue‐Matching Modulus for Real‐Time Sensing and Occlusion Monitoring

Treating vascular grafts failure requires complex surgery procedures and is associated with high risks. A real‐time monitoring vascular system enables quick and reliable identification of complications and initiates safer treatments early. Here, an electric fieldassisted 3D printing technology is developed to fabricate in situ‐poled ferroelectric artificial arteries that offer battery‐free real‐time blood pressure sensing and occlusion monitoring capability. The functional artery architecture is made possible by the development of a ferroelectric biocomposite which can be quickly polarized during printing and reshaped into devised objects. The synergistic effect from the potassium sodium niobite particles and the polyvinylidene fluoride polymer matrix yields a superb piezoelectric performance (bulk‐scale d₃₃ > 12 pC N^?1). The sinusoidal architecture brings the mechanical modulus close to the level of blood vessels. The desired piezoelectric and mechanical properties of the artificial artery provide an excellent sensitivity to pressure change (0.306 mV mmHg^?1, R² > 0.99) within the range of human blood pressure (11.25–225.00 mmHg). The high pressure sensitivity and the ability to detect subtle vessel motion pattern change enable early detection of partial occlusion (e.g., thrombosis), allowing for preventing grafts failure. This work demonstrates a promising strategy of incorporating multifunctionality to artificial biological systems for smart healthcare systems.     

A Tunable Polarization Field for Enhanced Performance of Flexible BaTiO3@TiO2 Nanofiber Photodetector by Suppressing Dark Current to pA Level

The flexible titanium dioxide (TiO₂) nanofibers (NFs) film are promising candidates for high-performance wearable optoelectronic devices. However, the TiO₂ ultraviolet photodetectors (UV PDs) generally suffer from low photosensitivity, which limits the practical applications. Herein, a TiO₂ (TO) NFs film flexible photodetector integrated by ferroelectric BaTiO₃ (BTO) NFs is developed via electrospinning technology with double sprinklers and in situ heat treatment. Compared with TO NFs PD with poor on/off ratio ≈44, the BTO@TO NFs PD-2 exhibits an excellent on/off ratio of ≈1.5  × 10⁴ due to the dramatically restrained dark current. The ultralow dark current (pA level) is attributed to the depletion of photogenerated carriers by the space high-resistance state induced by the downward self-polarization field in ferroelectric BaTiO₃ NFs. The ferroelectric domain with larger downward orientation in polarized BTO@TO NFs exhibits stronger self-polarization field to modify the directional transport of photogenerated carriers and enhances the band bending level, which improves the photocurrent of device. The special structure woven by ferroelectric nanofiber with self-polarization will provide a promising approach for improving the performance of flexible photodetectors.     

Photoexcited Ultraviolet-to-Infrared (II) Pyroelectricity in a 2D Ferroelectric Perovskite Driving Broadband Self-Powered Photoactivities

Photoexcited pyroelectricity in ferroelectrics allows the direct conversion of light radiation into electric signal without external power source, thus paving an avenue to promote optoelectronic device performances. However, it is urgently demanded to exploit new ferroelectrics with this attribute covering ultraviolet (UV)-to-infrared (IR) region for self-powered photodetection. Herein, broadband light-induced pyroelectric effects in a new 2D perovskite-type ferroelectric, (BBA)2(EA)2Pb3Br10 (1; BBA = p-bromobenzylammonium, EA = ethylammonium), showing a high Curie temperature of 425 K and notable pyroelectric coefficient (≈5.4 × 10⁻³ µC cm⁻² K⁻¹) is presented. Especially, photo-induced change of its electric polarization leads to ultraviolet-to-infrared pyroelectricity in a wide spectral region (377–1950 nm). Broadband photoactivities actualized by this property break the limitation of its optical bandgap. Thus, single-crystal detectors of 1 are sensitive to UV-to-IR light with a small temperature fluctuation of 0.3 K, exhibiting a high transient responsivity up to ≈0.28 mA W⁻¹ and specific detectivity of 1.31 × 10¹⁰ Jones under zero bias (at 405 nm); such figure-of-merits are beyond than those self-powered photodetectors using oxide ferroelectrics. It is anticipated that the findings of light-induced pyroelectricity afford a feasible strategy to assemble newly-conceptual smart photoelectric devices, such as self-powered broadband detectors.     

电场作用下聚合物网络稳定的铁电液晶分子排列的研究

通过扫描电子显微镜和偏光显微镜研究了在电场作用下聚合物网络稳定的铁电液晶分子取向特性。实验结果表明：铁电液晶盒内形成的聚合物网络具有方向性和规律性并为树枝状；由于在近晶Ｃ＊下进行聚合物网络紫外固化，并在固化过程中施加低频电场（±５０Ｖ，５Ｈｚ），从而有效地控制了铁电液晶分子的排列，改变了以往的铁电液晶显示器中的分子排列模式（Ｃｈｅｖｒｏｎ结构）而得到了以条纹织构为代表特征的准书架式结构。     

Space‐Charge‐Stabilized Ferroelectric Polarization in Self‐Oriented Croconic Acid Films

Great progress has been made recently in molecular ferroelectrics with properties even comparable to those of inorganic ferroelectrics. However, it is difficult to develop basic thin films and devices for practical applications since most molecular ferroelectrics are uniaxial. The single polar axes of crystallites inside their films, if available, are usually oriented randomly. These can induce the components without contribution to ferroelectric polarization and a large depolarization electric field to suppress polarization. In this work, it is demonstrated that uniaxial croconic acid films in two‐terminal devices, deposited by thermal evaporation, can show effective ferroelectric polarization and nonvolatile memory switching behavior with small coercive fields of 11–30 kV cm^?1. The polar c‐axes in thick crystalline films (>500 nm) are found to be self‐oriented nearly at a desired direction. With the assistance of trapped charges, stable ferroelectric polarization can be achieved, in spite of the existence of nonferroelectric components. These may pave a way to utilize uniaxial molecular ferroelectrics for various applications, such as gate dielectrics, electrets, and memory devices.