Zinc borate modified multifunctional ceramic diaphragms for lithium-ion battery

Polyethylene(PE) diaphragm has become broadly used in lithium-ion battery systems because of its high strength, exceptional plasticity, and resistance to organic solvents. Nevertheless, the lack of polar groups on the surface of the PE diaphragms has a little significant effect on the ionic polarity of the electrolyte. Consequently, the electrolyte has poor wettability, the lithium-ion migration number t_Li⁺ (0.21) and the ion conductivity σ (0.63 mS/cm) still need to be further improved, which restricts its application to a certain extent. In this work, the high-purity zinc borate modified PE diaphragms with Lewis acid sites were prepared via a simple solid-state method. The multifunctional diaphragms modified by zinc borate have the following advantages: (1) The Zn–O bond and -BO₃ group in the structure have a polar bond and Lewis acid action, respectively, which can promote the desolvation of lithium ions and the dissociation of anions and cations, thereby increasing the concentration of free ions. In addition, zinc borate and anions have a specific binding effect, which can inhibit the migration of anions, consequently increasing t_Li⁺ (0.41) and σ (1.14 mS/cm); (2) Zinc borate was a commonly used flame retardant, which was conducive to improving the thermal stability of the PE diaphragms; (3) The surface of the modified diaphragms is rougher, which can increase the specific surface area of the diaphragm, hence enhancing its liquid absorption capacity. The electrochemical performance test results show that the modification of zinc borate can effectively improve the comprehensive performance of the PE diaphragm and the overall cycle stability and rate performance of the lithium iron phosphate battery.     

Influence of sintering atmosphere on the phase,microstructure, and lithium-ion conductivity of the Al-doped Li7La3Zr2O12 solid electrolyte

Al-doped Li₇La₃Zr₂O₁₂ (Al–LLZO) solid electrolytes were sintered at 1150 ^°C for 8 h in atmosphere of oxygen, argon and air (named as Al–LLZO–O₂, Al–LLZO–Ar and Al–LLZO–Air, respectively). All the Al–LLZO samples exhibited a single cubic garnet-type structure. The sample of Al–LLZO–O₂ possessed the highest relative density (95.60%) and the largest average grain size among the three Al–LLZO samples. Furthermore, owing to its high relative density and small number of grain boundaries, Al–LLZO–O₂ demonstrated a higher lithium-ion conductivity than Al–LLZO–Ar and Al–LLZO–Air.     

ChCl-urea-ZnO低共熔溶剂体系的电化学行为

研究了ChCl-urea-ZnO低共熔溶剂（DES）体系的电化学行为与ZnO浓度的相互关系。电导率测定结果表明，ChCl-urea-ZnO体系的电导率随ZnO浓度的增加而增大，但当ZnO浓度超过0.24 mol·L^-1，体系电导率趋于稳定。随着温度的升高，ChCl-urea-ZnO的电导率增大，电导率与温度的关系符合Kohlraush经验公式。循环伏安测试结果表明，在ChCl-urea-ZnO低共熔体系中，Zn（Ⅱ）还原为金属锌是受扩散控制的准可逆过程，Zn（Ⅱ）的扩散系数约为1.2×10^-7 cm²·s^-1。而且金属锌的析出电位随ZnO浓度的增加而正移，峰值电流明显增大，说明增大ZnO浓度有利于锌的沉积。此外，ZnO浓度对锌沉积层的形貌有明显影响，不同ZnO浓度下得到锌沉积物的形貌各不相同，有短棒状、方形等。     

Phytochemical bioaccessibility and in vitro antidiabetic effects of Chinese sumac (Rhus chinensis Mill.) fruits after a simulated digestion: insights into the mechanisms with molecular docking analysis

This work studied the effects of gastrointestinal digestion on the phytochemical bioaccessibility and in vitro anti-diabetic effects of different fractions from Chinese sumac fruits and delineated the underlying mechanisms by molecular docking. Results showed that gastric digestion significantly increased the phytochemical bioaccessibility and inhibitions for α-glucosidase, dipeptidyl peptidase-4 (DPP-IV) and advanced glycation end product (AGE) formation of the ethanol-extracted fraction, whereas intestinal digestion remarkably decreased these parameters (P < 0.05). For the free phenolic fraction, the parameters were remarkably reduced after gastric digestion but significantly increased after intestinal digestion (P < 0.05). Quercitrin and gvajaverin contributed the most to the α-glucosidase and DPP-IV inhibitions, and trigalloyl glucose and its isomer could be the primary bioactive substance responsible for AGE suppression. Quercitrin, the predominant phenolic compound, could effectively interact with crucial amino acid residues in α-glucosidase, DPP-IV and bovine serum albumin with hydrogen bonds and hydrophobic interactions to exert its inhibitions.     

食品中鲜味肽的研究进展

鲜味肽作为新型的鲜味剂，除了本身具有的风味外，还可与其他的鲜味物质发挥协同增鲜作用。目前对鲜味肽的研究主要集中在提取及分离鉴定等方面，而鲜味肽的形成机理及呈味机制仍不明确。本文对鲜味肽的制备与分离鉴定方法、呈味影响因素、鲜味评价方法、具体应用、呈味机制等方面进行综述，以期为鲜味肽的进一步深入研究提供科学理论依据。     

附加减震结构加固主结构的减震控制方法、特性及实例分析

为使主结构的建筑功能与减震性能得到同时提升，提出了一种使用附加减震结构加固主结构的理论分析模型及关键参数算法。通过令主结构无阻尼幅频曲线峰值在不动点处取得最小值，得出了主结构的减震频率控制方程及附加结构的阻尼比计算式。利用数值方法，分析了主结构的幅频曲线特性。结果表明：主结构幅频曲线上的不动点在频域范围存在极限位置，使得主结构的最小幅频峰值在频域内有极限位置；主结构的减震性能有一定频率相关性；附加结构阻尼比数值能达到的前提下，质量比、耦连频率比及主结构阻尼比越大时，主结构的减震效果越好。运用该减震控制方法的工程实例分析结果表明，由简化模型所得的减震控制方法能够运用于以一阶模态控制的多自由度体系，并使得加固后的主结构最大层间位移角降低29.56%。     

紫茎泽兰茎燃烧性与土壤有效磷含量的关系

以滇中地区的紫荆泽兰茎为研究对象，测定了紫茎泽兰茎的粗脂肪含量、灰分含量、热值以及紫荆泽兰根系土壤有效磷含量。以粗脂肪含量、灰分含量以及热值为评价指标，计算了紫茎泽兰茎的燃烧性综合指数，并分析了紫茎泽兰粗脂肪含量、灰分含量、热值以及燃烧性综合指数与土壤有效磷含量的关系。研究表明，紫茎泽兰茎的粗脂肪含量、热值以及燃烧性综合指数与土壤有效磷含量呈正相关关系的比例分别为65.22% 、52.17% 和56.52% ，灰分含量与土壤有效磷含量呈负相关的比例为60.87%。土壤有效磷含量可在一定程度上增加紫茎泽兰茎的粗脂肪含量、热值，降低其灰分含量，并增强其燃烧性。     

Evaluation of biphasic calcium phosphate/nanosized 3YSZ composites as toughened materials for bone substitution

In this research, biphasic calcium phosphate (BCP), comprising 70 wt% of beta tricalcium phosphate and 30 wt% of hydroxyapatite, was mixed with different amounts of 3 mol% yttria-stabilized zirconia (3YSZ) and sintered at 1200 °C to produce toughened bone substitutes. The fracture toughness (K_Ic) of the obtained bodies was determined using the indentation-strength fracture method. Scanning electron microscopy and energy dispersive X-ray spectroscopy analysis were utilized to study the microstructure of the samples. The phase composition of the samples was also determined using X-ray diffraction technique. In order to investigate the cell supporting ability of the samples, G-292 cells were cultured on them and cell morphology was evaluated after 48 h. Based on the results, the maximum fracture toughness and compressive strength values (i.e., 2.11 MPa m^0.5 and 150 MPa, respectively) were obtained for the sample containing 3 vol% of 3YSZ. The obtained fracture toughness value was approximately two times higher than that of the original BCP (1.07 MPa m^0.5) and also was comparable with that of the cortical human bone. The following mechanisms for the improved K_Ic of the β-tricalcium phosphate were determined: Grain bridging of 3YSZ particles during crack growth resistance, formation of microcracks on the tip of the larger cracks, absorbing crack extension energy due to the volume expansion during 3YSZ tetragonal-monoclinic transformation and crack deflection by the presence of 3YSZ particles. Also, 3YSZ additive encourages transformation of HA phase into β-TCP during sintering BCP. Finally, based on the cell studies, the samples exhibited an adequate cell attachment and a good cell spreading condition.