超声波-酶法协同制备梅花鹿鹿血肽及其体内抗疲劳活性研究

目的采用超声波辅助生物酶法协同制取鹿血肽,研究酶解条件对鹿血肽得率的影响。方法通过单因素和正交实验优化混合蛋白酶不同酶解时间、酶解温度、加酶量、pH。以小鼠游泳时间为指标,研究鹿血多肽的抗疲劳活性。结果鹿血酶解的温度为50℃、酶解时间为4.0 h、加酶量5.5%、pH 7.5为较优酶解条件,此时水解度为29.10%。小鼠抗疲劳实验显示:鹿血多肽高、中、低剂量组小鼠游泳力竭时间延长率分别为159.46%、91.89%、13.51%,与对照组相比,鹿血多肽高、中剂量组游泳力竭时间均显著延长(P<0.05);鹿血多肽高剂量组小鼠游泳力竭后,解剖检测发现肝脏中肝糖原含量以及血液中的尿素氮浓度、乳酸含量均显著提升(P<0.05),明显提高运动后小鼠机体代谢活动,增强其抗疲劳能力。结论本研究为进一步研究梅花鹿鹿血肽的抗疲劳机制和开发鹿血肽酒等相关产品奠定了基础。

国家药品应急体系的问题与对策

由中国药学会承担的“国家药品应急体系建设研究”是国家“十二五”规划前期重大问题研究课题之一，课题组通过广泛的调研，了解了我国目前药品应急体系建设的现状，查找存在的问题，分析环境因素的影响。课题组构建了我国药品应急体系的“需求一供给一筹资”分析模型并分析了各种环境因素对应急药品的需求、供给和筹资带来的复杂影响，形成了“一个体系，四个保障平台”的药品应急体系建设构想，为完善我国药品应急体系建设奠定强有力的基础。

不同干燥方式对柳蒿芽山野菜挥发性风味的影响研究

为研究不同干燥方式对柳蒿芽山野菜中的挥发性风味化合物影响的差异性,采用气相色谱-离子迁移谱联用(GC-IMS)技术对3种不同干燥处理的柳蒿芽样品进行挥发性化合物检测分析。从样品中共检出103种挥发性有机化合物(volatile organic compounds,VOCs);经归一化处理,结合指纹图谱分析,真空冷冻干燥样品中93种VOCs得到了有效的保留,显著高于电热鼓风干燥和自然干燥组,根据气味描述数据库检索可知冷冻干燥对柳蒿芽中的甜香、焦香气味有较好的保留。正交偏最小二乘法判别分析(OPLS-DA)结果筛选出了12种对区分不同干燥方式的柳蒿芽挥发性风味物质贡献较大的变量,分别为十二醛、2-甲基异冰片、1-辛醇、薄荷脑、(E,E)-2,4-庚二烯醛、乙酸冰片酯、香茅醛、DL-2-羟基-4-甲基戊酸乙酯、1-石竹烯、三亚乙基二胺。

不同肉酱比鹿肉酱中关键挥发性有机化合物的判别分析

目的探究不同肉酱比对鹿肉酱中挥发性有机化合物(volatile organic compounds,VOCs)影响的差异性,并筛选不同肉酱比的关键性VOCs。方法利用电子鼻结合气相色谱-离子迁移谱法(gas chromatography-ion mobility spectrometry,GC-IMS)检测不同肉酱比加工的鹿肉酱样品中的香气类别及VOCs成分,通过计算偏最小二乘法判别(partial least squares discriminant analysis,PLS-DA)和正交-偏最小二乘法判别(orthogonal partial least squares discriminant analysis,OPLS-DA)分析变量重要性因子(variable important for the projection,VIP),筛选可区分不同肉酱比的鹿肉酱样品中差异性影响最关键的变量敏感物质及VOCs(VIP>1)。结果电子鼻传感器S3、S7、S9和S10对应的氨类、芳香族、硫化物和萜烯类、芳香族、硫化氢类、烷烃类等敏感物质是不同肉酱比的鹿肉酱样品中最关键的挥发类特征性气味;利用GC-IMS共检测出82种主要VOCs,筛选出33种关键差异性特征VOCs(VIP>1),与电子鼻的关键特征性香气检测结果一致。结论基于电子鼻和GC-IMS的主要特征香气标志物的聚类分析能够有效、全面、客观地对不同肉酱比的鹿肉酱中关键挥发性性气味和VOCs进行区分和评价。

保加利亚乳杆菌发酵转化人参皂苷工艺研究

目的以人参为原料,通过保加利亚乳杆菌发酵提高人参皂苷含量。方法利用单因素试验和响应面法优化发酵工艺,并对发酵过程中原型人参皂苷生物转化可能途径进行分析。结果在发酵培养基为MRS液体培养基的前提下,最适发酵条件为发酵温度40℃,发酵时间3d,接种量3%,转化稀有人参皂苷含量在150μg/mL。经对比发现,原参中检测出Re、Rg1、Rb1、Rc、Rb2、Rd、Rh17种皂苷,经过发酵后的人参中检测出Re、Rg1、Rb1、Rc、Rb2、Rh1、Rd、R-rg3、CK 9种皂苷。同时原参中的常规皂苷含量经发酵后有所下降,稀有皂苷含量有所增加,且总酚、黄酮含量增加,总糖含量减少,发酵过程中人参皂苷生物转化的可能途径与人参皂苷含量变化趋势一致。结论保加利亚乳杆菌发酵人参能够有效将原型皂苷转化成稀有人参皂苷,为人参的深加工奠定基础,为人参发酵产品的开发和利用提供参考。

人参不定根中皂苷对小鼠脂质代谢的影响研究

目的研究人参不定根皂苷对小鼠脂质代谢的影响。方法将小鼠随机分成5个实验组(共50只,每组10只),分别为正常组(生理盐水)、对照组(生理盐水)、人参不定根皂苷低(50 mg/kg)、中(100 mg/kg)、高(200 mg/kg)剂量组,连续灌胃30 d,测定小鼠血脂、肝损伤和抗氧化指标。结果与高脂对照模型组相比,人参不定根皂苷高剂量组甘油三酯、总胆固醇显著降低(P<0.05)、低密度脂蛋白胆固醇极显著降低(P<0.01);中、高剂量组谷草转氨酶和谷丙转氨酶含量极显著降低(P<0.01);中、高剂量组总超氧化物歧化酶活性极显著升高(P<0.01)、丙二醛含量极显著降低(P<0.01)。结论人参不定根皂苷能够促进高脂饲料诱导高脂血症小鼠机体代谢,降低血脂,修复肝损伤,降低过氧化损伤,增强抗氧化能力。

黑参甜米酒加工工艺优化及挥发性成分测定

目的优化黑参甜米酒加工工艺,测定其挥发性成分。方法以黑参添加量、甜酒曲添加量、发酵时间、发酵温度进行单因素试验,通过正交试验确定最佳工艺。结果在黑参添加量为4%、甜酒曲添加量为2.0%、发酵温度30℃、发酵时间为72 h时的条件下感官评分最高,酒精度为15%vol,其理化指标及微生物指标符合相关标准。所得黑参甜米酒酒香浓郁并伴有黑参特有的香气,口感醇厚、色泽清亮。通过顶空-气相色谱-离子迁移谱法(headspace gas chromatography ion mobility spectrometry,HS-GC-IMS)分析,共鉴定出36个挥发性成分,其中成分明确的有29种,酸类6种、烃类2种、醇类6种、酯类4种、酚类1种、醛类7种、酮类3种。结论以黑参和糯米为原料制备黑参甜米酒,通过对黑参米酒加工工艺的优化,得到适宜的加工条件,通过HS-GC-IMS测定米酒中的挥发性成分,为新型米酒成分的分析提供参考,为米酒赋予黑参特有的保健功能。

大豆分离蛋白基参菌薄片生产工艺优化及其理化特性分析

目的基于大豆分离蛋白、木耳、榛蘑、元蘑、滑子蘑和人参等原料加工制成大豆分离蛋白基参菌薄片。方法采用单因素及响应面试验法优化大豆分离蛋白基参菌薄片生产工艺,并对其理化特性进行检测分析。结果在参菌粉粒度210目、人参粉添加量3.1%、涂膜厚度0.8mm和海藻酸钠添加量8.41%的条件下,产品感官评分最高,达94.7分。理化特性分析表明产品中蛋白质、脂肪和灰分含量分别为39.14 g/100 g、3.98 g/100 g和5.84 g/100 g,并且含多种氨基酸。产品中人参皂苷Rb1、Re+Rg1和总皂苷含量分别为0.25 g/100 g、0.30 g/100 g和0.88 g/100 g。结论影响大豆分离蛋白基参菌薄片感官评分的因素由大到小依次是参菌粉粒度、涂膜厚度、人参粉添加量、海藻酸钠添加量。本产品为即食产品,营养丰富,市场前景广阔。

“阳明心学”与徐渭“真我”观的生成——心学视域下徐渭抒情思想研究之一

“阳明心学”深刻影响了明以后中国抒情思想的发展,徐渭即为一典型。徐渭参与阳明心学的学习活动,并为阳明复爵进行申诉,得以成功。徐渭亦像阳明一样,在形成心学为魂的中心思想时,多方参照道、佛思想,体现了思想上的开放性。尤其是形成的“真我”观,初看近似道、佛,实以心学的本体自我论为依据,为其形成求真重情、狂放不羁的艺术个性与创立大写意水墨画提供了哲学基础,代表中国文论中抒情主体论的一次重要发展与提升。五四时期的现代自我论正是承续心学本体自我论而转型成功。

Electrolyte engineering for optimizing anode/electrolyte interface towards superior aqueous zinc-ion batteries:A review

Aqueous zinc-ion batteries(AZIBs) are promising candidates for the large-scale energy storage systems due to their high intrinsic safety,cost-effectiveness and environmental friendliness.However,issues such as dendrite growth,hydrogen evolution reaction,and interfacial passivation occurring at the anode/electrolyte interface(AEI) have hindered their practical application.Constructing a stable AEI plays a key role in regulating zinc deposition and improving the cycle life of AZIBs.The fundamentals of AEI and the challenges faced by the Zn anode due to unstable interfaces are discussed.A comprehensive summary of electrolyte regulation strategies by electrolyte engineering to achieve a stable Zn anode is provided.The effectiveness evaluation techniques for stable AEI are also analyzed,including the interfacial chemistry and surface morphology evolution of the Zn anode.Finally,suggestions and perspectives for future research are offered about enabling a durable and stable AEI via electrolyte engineering,which may pave the way for developing high-performance AZIBs.

Microstructure and ablation behavior of Zr-based ultra-high-temperature gradient composites

To obtain high-performance Zr-based ultra-high-temperature composites,Zr-based ultra-high-temperature gradient composites were prepared by changing the laying method of the infiltrant via reactive melt infiltration.The effects of different infiltrant laying methods on the microstructure and ablative properties of Zr-based ultrahigh-temperature gradient composites were investigated.The results showed that the gradient structure of the Zr-based ultrahigh-temperature gradient composites differed when the composition ratio of the infiltrant was changed.When the thicknesses of the Zr/Mo/Si layers were 6/4/12 mm and 8/2/12 mm,the SiMoZrC solid solution content in the samples increased and decreased along the infiltration direction,respectively.The gradient samples were ablated in an oxyacetylene flame at 3000°C for 40 s.The ablation resistance of the sample was the highest when the infiltrant was a powder and the thickness of the Zr/Mo/Si layer was 6/4/12 mm.

Phase transformation in titanium alloys:A review

Due to a series of exceptional properties,titanium and titanium alloys have received extensive attention in recent years.Different from other alloy systems,there are two allotropes and a sequence of metastable phases in titanium alloys.By summarizing the recent investigations,the phase transformation processes corresponding to the common phases and also some less reported phases are reviewed.For the phase transformation only involvingαandβphases,it can be divided intoβ→αtransformation and a reverse transformation.The former one has been demonstrated from the orientation relationship betweenαandβphases and the regulation ofαmorphology.For the latter transformation,the role of the stress has been discussed.In terms of the metastable phases,the mechanisms of phase formation and their effects on microstructure and mechanical properties have been discussed.Finally,some suggestions about the development of titanium alloys have been proposed.

Ab initio molecular dynamics simulation reveals the influence of entropy effect on Co@BEA zeolite-catalyzed dehydrogenation of ethane

The C–H bond activation in alkane dehydrogenation reactions is a key step in determining the reaction rate.To understand the impact of entropy,we performed ab initio static and molecular dynamics free energy simulations of ethane dehydrogenation over Co@BEA zeolite at different temperatures.AIMD simulations showed that a sharp decrease in free energy barrier as temperature increased.Our analysis of the temperature dependence of activation free energies uncovered an unusual entropic effect accompanying the reaction.The unique spatial structures around the Co active site at different temperatures influenced both the extent of charge transfer in the transition state and the arrangement of 3d orbital energy levels.We provided explanations consistent with the principles of thermodynamics and statistical physics.The insights gained at the atomic level have offered a fresh interpretation of the intricate long-range interplay between local chemical reactions and extensive chemical environments.

Single-atom modified graphene cocatalyst for enhanced photocatalytic CO_(2) reduction on halide perovskite

Metal halide perovskite(MHP)has become one of the most promising materials for photocatalytic CO_(2) reduction owing to the wide light absorption range,negative conduction band position and high reduction ability.However,photoreduction of CO_(2) by MHP remains a challenge because of the slow charge separation and transfer.Herein,a cobalt single-atom modified nitrogen-doped graphene(Co-NG)cocatalyst is prepared for enhanced photocatalytic CO_(2) reduction of bismuth-based MHP Cs_(3)Bi_(2)Br_(9).The optimal Cs_(3)Bi_(2)Br_(9)/Co-NG composite exhibits the CO production rate of 123.16μmol g^(-1)h^(-1),which is 17.3 times higher than that of Cs_(3)Bi_(2)Br_(9).Moreover,the Cs_(3)Bi_(2)Br_(9)/Co-NG composite photocatalyst exhibits nearly 100% CO selectivity as well as impressive long-term stability.Charge carrier dynamic characterizations such as Kelvin probe force microscopy(KPFM),single-particle PL microscope and transient absorption(TA)spectroscopy demonstrate the vital role of Co-NG cocatalyst in accelerating the transfer and separation of photogenerated charges and improving photocatalytic performance.The reaction mechanism has been demonstrated by in situ diffuse reflectance infrared Fourier-transform spectroscopy measurement.In addition,in situ X-ray photoelectron spectroscopy test and theoretical calculation reveal the reaction reactive sites and reaction energy barriers,demonstrating that the introduction of Co-NG promotes the formation of ^(*)COOH intermediate,providing sufficient evidence for the highly selective generation of CO.This work provides an effective single-atom-based cocatalyst modification strategy for photocatalytic CO_(2) reduction and is expected to shed light on other photocatalytic applications.

Effects of anions on the structural regulation of Zn‑salen‑modified metal‑organic cage

By virtue of a 3∶1 complementary coordination strategy,a chiral heteroleptic metal-organic cage that con-tains divergent functional units,Pd‑R(Zn),was precisely constructed via self-assembly of monodentate variational Zn-salen ligands RZn and NADH(reduced nicotinamide adenine dinucleotide)mimic modified tridentate ligands with square-planar Pd ions.UV-Vis and luminescence spectra experiments reveal that different anions could selec-tively interact with different sites of Zn-salen modified metal-organic cages to achieve the structural regulation of cage compound,by using the differentiated host-guest electrostatic interactions of counter ions with metal-organic hosts.Compared to other anions,the presence of chloride ions caused the most significant fluorescence emission enhancement of Pd‑R(Zn),meanwhile,the UV-Vis absorption band attributed to the salen aromatic backbone showed an absorption decrease,and the metal-to-ligand induced peak displayed a blue shift effect.Circular dichro-ism and ^(1)H NMR spectra further demonstrate that the introduction of chloride anions is beneficial to keeping a more rigid scaffold.

Higher-order mode analysis for SOLEIL-type superconducting cavity

A 499.8 MHz SOLEIL-type superconducting cavity was simulated and designed for the first time in this paper.The higher-order mode(HOM)properties of the cavity were investigated.Two kinds of coaxial HOM couplers were designed.Using 4 L-type and 4 T-type HOM couplers,the longitudinal impedance and the transverse impedances were suppressed to below 3 kΩand 30 kΩ/m,respectivly.The HOM damping requirements of Hefei Advanced Light Facility(HALF)were satisfied.This paper conducted an in-depth study on the radio frequency(RF)design,multipacting optimization,and thermal analysis of these coaxial couplers.Simulation results indicated that under operating acceleration voltage,the optimized couplers does not exhibit multiplicating or thermal breakdown phenomena.The cavity has the potential to reach a higher acceleration gradient.

Tailoring the microenvironment of Ti sites in Ti-containing materials for synergizing with Au sites to boost propylene epoxidation

Au sites supported on Ti-containing materials(Au/Ti-containing catalyst)are currently considered as a promising catalyst for the propylene epoxidation owing to the synergistic effect that hydrogen peroxide species formed on Au sites diffuses to the Ti sites to form the Ti-hydroperoxo intermedi-ates and contributes to the formation of propylene oxide(PO).In principle,thermal treatment will significantly affect the chemical and physical structures of Ti-containing materials.Consequently,the synergy between tailored Ti sites with different surface properties and Au sites is highly expected to enhance the catalytic performance for the reaction.Herein,we systematically studied the intrinsic effects of different microenvironments around Ti sites on the PO adsorption/desorption and conversion,and then effectively improved the catalytic performance by tailoring the number of surface hydroxyl groups.The Ti^(Ⅵ) material with fewer hydroxyls stimulates a remarkable enhancement in PO selectivity and H_(2) efficiency compared to the Ti^(Ⅵ) material that possessed more hydroxyls,offering a 7-fold and 4-fold increase,respectively.As expected,the Ti^(Ⅵ+Ⅳ) and Ti^(Ⅳ) materials also exhibit a similar phenomenon to the Ti^(Ⅵ) materials through the same thermal treatment,which strongly supports that the Ti sites microenvironment is an important factor in suppressing PO con-version and enhancing catalytic performance.These insights could provide guidance for the rational preparation and optimization of Ti-containing materials synergizing with Au catalysts for propylene epoxidation.

Enhancing selectivity in acidic CO_(2) electrolysis:Cation effects and catalyst innovation

The electrochemical reduction of CO_(2)(eCO_(2)R)under ambient conditions is crucial for reducing carbon emissions and achieving carbon neutrality.Despite progress with alkaline and neutral electrolytes,their efficiency is limited by(bi)carbonates formation.Acidic media have emerged as a solution,addressing the(bi)carbonates challenge but introducing the issue of the hydrogen evolu-tion reaction(HER),which reduces CO_(2) conversion efficiency in acidic environments.This review focuses on enhancing the selectivity of acidic CO_(2) electrolysis.It commences with an overview of the latest advancements in acidic CO_(2) electrolysis,focusing on product selectivity and electrocatalytic activity enhancements.It then delves into the critical factors shaping selectivity in acidic CO_(2) electrolysis,with a special emphasis on the influence of cations and catalyst design.Finally,the research challenges and personal perspectives of acidic CO_(2) electrolysis are suggested.

Boosting photocatalytic hydrogen evolution enabled by SiO_(2)-supporting chiral covalent organic frameworks with parallel stacking sequence

Two-dimensional covalent organic frameworks(2D COFs)feature extendedπ-conjugation and ordered stacking sequence,showing great promise for high-performance photocatalysis.Periodic atomic frameworks of 2D COFs facilitate the in-plane photogenerated charge transfer,but the precise ordered alignment is limited due to the non-covalentπ-stacking of COF layers,accordingly hindering out-of-plane transfer kinetics.Herein,we address a chiral induction method to construct a parallelly superimposed stacking chiral COF ultrathin shell on the support of SiO_(2) microsphere.Compared to the achiral COF analogues,the chiral COF shell with the parallel AA-stacking structure is more conducive to enhance the built-in electric field and accumulates photogenerated electrons for the rapid migration,thereby affording superior photocatalytic performance in hydrogen evolution from water splitting.Taking the simplest ketoenamine-linked chiral COF as a shell of SiO_(2) particle,the resulting composite exhibits an impressive hydrogen evolution rate of 107.1 mmol g^(-1)h^(-1)along with the apparent quantum efficiency of 14.31% at 475 nm.Furthermore,the composite photocatalysts could be fabricated into a film device,displaying a remarkable photocatalytic performance of 178.0 mmol m^(-2)h^(-1)for hydrogen evolution.Our work underpins the surface engineering of organic photocatalysts and illustrates the significance of COF stacking structures in regulating electronic properties.