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关键词： 一流课程   建设标准   重要特征   建设经验  

摘要： 一流课程建设是一流本科建设的基础。本文首先基于对一流课程“两性一度”标准的认识,指出定位准确、目标清晰、基础良好、理念先进、建设一流、效果显著、示范引领是一流课程建设的关键特征,而后以山东大学物理化学一流课程建设为例,介绍了课程定位和教学目标的确定和设计落实,介绍了课程在一流基础、一流师资、一流资源、一流理念、一流成效等5个方面开展建设的做法和经验。对未来各高校开展一流课程建设具有一定的借鉴意义。

关键词： Sanchi flower powders   Superfine grinding   Physiochemical properties  

摘要： Sanchi flowers were traditionally used as functional medicinal ingredient in materials. The study was aimed at evaluating superfine powder product of Sanchi flower, hence in this study, five fractions of dried Sanchi flower powders (SFP) were prepared at variable particle sizes by superfine grinding and evaluated for changes in various properties. Superfine powder with median particle diameter of 25.57 mu m was produced through grinding. It was evident from the environmental scanning electron microscopy analysis that during superfine grinding, mechanical shear stress played its crucial role in breakdown of the SFP and causes increases in surface area owing to reduction of particle sizes. Superfine grinding could improve solubility, oil holding capacity, and brightness, but decrease the fluidity of SFP. SFP with smallest particle size exhibited highest saponin, minerals, total phenolic, and flavonoid contents accompanied with the best antioxidant activities. Size reduction beyond M200 and M400 led to increasing tendency in IR signature band patterns and marked differences in peak intensities while the powdered samples showed resemblance with respect to peak shapes. Differential scanning calorimetry indicated the lowest melting temperature for SFP fraction with smallest particle size. Conclusively, superfine SFP due to inherent improvement in properties may render several potential applications in manufacturing of food and pharmaceutical additives to impart improved functionalities of finally finished products with uniformity.

关键词： Adhesion   Dentin   Collagen   Degradation  

摘要： Objectives: To evaluate the incorporation of doxycycline (DOX) into a commercial dental adhesive regarding physicochemical properties, microtensile bond strength (mu TBS), nanoleakage (NL), nanohardness (NH) and Young's modulus (YM), metalloproteinases (MMP) inhibition, and antibiofilm activity. Methods: DOX was incorporated into the adhesive at 0.05, 0.1, 0.5, and 1 wt%. Restored teeth were evaluated for mu TBS, NL, NH, and YM after 24 -hs and 1-year of water storage. Biofilms of Streptococcus mutans were grown on top of these adhesives and determined for bacterial viability and amount of biomass. The inhibitory effect on MMP was analyzed by in situ zymography under confocal microscopy. Results: Adhesives with 0.5 and 1 wt% of DOX presented reduced pH and degree of conversion. The incorporation of DOX did not affect mu TBS and hybrid layer YM. The control group (no DOX) had a decrease in mu TBS and the densest silver nitrate areas after 1-year storage. Hybrid layer NH values increased with 0.1 wt% DOX compared to control and 1 wt% DOX groups, at 24 -hs. After 1-year storage, NH of 1 wt% DOX adhesive decreased compared to the control group. The 0.5 and 1 wt% concentrations of DOX decreased the bacterial viability and the biofilm biomass. Confocal images suggest an increased MMP inhibition proportional to the percentage of DOX. Conclusion: At any concentration, DOX-doped dental adhesives were able to inhibit MMP activity, diminish nanoleakage, and maintain the resin-dentin bond-strength after 1 year of artificial aging. Clinical significance: Doxycycline-doped dental adhesive inhibited metalloproteinases activity and preserved interface bond strength. This formulation has a potential to improve adhesive restorations clinical longevity.

关键词： activated adsorbent   humic acids   electrophysical properties   capacitance   electrical resistance   dielectric constant  

摘要： The chemical analysis of humic acids and their activated forms based on brown coal from the Maikuben coal basin (Kazakhstan) was carried out. The humic acids were obtained on the basis of potassium humates. Activated humic acids (AHAs) were prepared by carbonization and activation in argon and water vapor atmospheres at 873 K, and the physicochemical characteristics and surface morphology of the test samples were studied. The electrical resistance (R), electric capacitance (C), and dielectric constant (epsilon) of the samples in a temperature range of 293-483 K were determined for the first time. The samples obtained were tested as an adsorbent for water treatment in order to remove heavy metals.

关键词： corn starches   heat-moisture treatment   lactic acid modification   principal component analysis   treatment temperature  

摘要： Native corn starch is subjected to dual heat moisture (30 g per 100 g d.b.)/lactic acid (10 g per 100 g d.b.) treatment (HMLAx) at different temperatures (x= 90, 110, 130, and 150 degrees C), and is compared with heat moisture (HMx) treatment alone. Neither HMLAx nor HMx change the crystallinity type (A-type) of the corn starch, but the relative crystallinity is lowered by 60-80%. Both treatments reduce the gelatinization enthalpy, but it is higher for HMLAx (approximate to 70%), and induces reductions in rapidly digestible starch (up to approximate to 70%) and increases in slowly digestible starch (up to approximate to 35%) and resistant starch (RS) fractions. The variations are temperature dependent. A principal component analysis is carried out (9 formulations, 17 variables), showing that heat moisture and lactic acid act independently (p< 55%) in the modification of starch, giving rise to different physicochemical (solubility, viscoelasticity, relative crystallinity), thermal, and in vitro digestibility properties.

关键词： 物理化学   高等学校   教材  

ISBN: (纸本)9787568025058

摘要： 本书为普通高等学校“十四五”规划药学类专业特色教材。本书除绪论外，共分为八章，涵盖了化学热力学、化学动力学、表面现象、相平衡、溶胶、大分子溶液、电化学基础等基本内容，系统阐述了相关的基本理论、基本知识、基本方法及有关应用。本书每章设有学习目标、本章小结、知识拓展、目标检测与习题等板块，相关的数字资源有课件、目标检测与习题答案等。为方便读者复习及检验学习效果，书后附有各参编院校提供的模拟试卷（附参考答案）。本书可以作为普通高等学校药学类专业的物理化学课程教材，也可作为其他专业学生或教师的参考书。

关键词： Lignin   Physicochemical characterization   Biorefinery  

摘要： The mechanisms behind lignin dissolution with protic ionic liquids (PILs) and their influence over lignin properties remain not fully explored. In this work, physicochemical and structural features of lignins extracted from sugarcane bagasse after pretreatment with a series of PILs (length of the cation chain combined with different anions) were assessed using analytical techniques. It was found that the lignin extracted with shorter chain length cations PILs showed the highest beta-O-4 content. Opposite, the increase of the PILs cation chain length resulted in enhanced depolymerization. All lignins presented high polydispersity (>3.7), while the weight average molecular ranged from 1921 to 13,539 g/mol. The recovered [Eti][Mal] lignin presented the higher beta-O-4 content and was possibly the most preserved lignin obtained. Opposite, lignin isolated from [Hex][Ac] and [Hex][For] treatments had less beta-O-4 linkages attributed to the depolymerization of lignin via rupture of ether linkages generating intermediates that further repolymerized and/or depolymerized. These results suggest that the ionicity of the PIL is a crucial factor for lignin dissolution. Furthermore, these results illustrate that the proposed pretreatment using different PILs is useful to obtain high-quality lignins with distinct features and opens a new perspective for materials to match various applications.

关键词： goat cheese   starter culture   physicochemical and textural characteristic   volatile compound  

摘要： Today, cheese is valued because of its high nutritional value and unique characteristics. Improving the texture and flavor of cheese by selecting suitable starter cultures is an important way to promote the development of cheese industry. The effect of starter cultures on the physicochemical and textural properties and volatile compounds during the ripening of seminar goat cheese were investigated in this work. Different starter cultures-mesophilic (M) and thermophilic starters (T), Lactobacillus plantarum ssp. plantarum ATCC 14917 (Lp), a mix of the M arid T starters (M1), arid rriix of the M, T, and Lp starters (M2)-were used in the production of the goat cheeses. Volatile compounds were determined by a solid-phase microextraction/gas chromatography-mass spectrometric (SPME/GC-MS) method. The results showed that the moisture content of cheeses produced with the 5 kinds of starter cultures decreased after maturation, whereas ash content increased. The pH values of goat cheeses decreased first and then increased during maturity, and the pH value of M2 cheese was the lowest among the cheeses. The hardness and chewiness of the cheeses increased with increasing maturity, whereas cohesiveness, springiness, and resilience showed the opposite tendency. The 60-d-old cheese made with Lp had the highest chewiness, cohesiveness, springiness, and resilience, whereas the 60-d-old cheese made with M2 had the highest hardness. A total of 53 volatile components were identified by SPME/GC-MS, and carboxylic acids, alcohols, ketones, and esters were the 4 major contributors to the characteristic flavors of the cheeses. Volatile components and their contents differed greatly among the produced cheeses. The M2 cheese contained the highest relative content of the main volatile compounds (90.10%), especially butanoic acid arid acetoin. Through a comprehensive comparison of the results, we concluded that M2 cheese had a dense texture arid milky flavor, arid M2 is a potential starter cult

关键词： Linoleic acid  

摘要： The oil contents of almond kernels were determined between 37.60% (Selection 25) and 49.10% (Tuono). Total carotenoid and total flavonoid contents of almond kernels varied between 0.21 mu g/g (Nessebar) and 1.85 mu g/g (Teteny Botermo) to 44.75 mg/100 g (Selection 25) and 479.13 mg/100 g (Teteny Rekord), respectively. In addition, total phenolic contents and antioxidant activity values of almond kernels changed between 6.04 mg GAE/100 g (Ne Plus Ultra) and 83.19 mg GAE/100 g (Teteny Rekord) to 4.55% (Selection 25) and 90.15% (Teteny Rekord), respectively. Oleic acid contents of almond kernel oils were determined between 61.39% (Ne Plus Ultra) and 73.51% (Texas), linoleic acid contents of oil samples varied between 16.02% (Masbovera) and 30.60% (Ne Plus Ultra). Gallic acid, 3,4-dihydroxybenzoic acid, (+)-catechin, 1,2-dihydroxybenzene, syringic acid, caffeic acid, and quercetin were the key phenolic constituents of kernels showed partly differences depending on almond varieties. Almond kernels are rich in K, P, Ca, Mg, Na, and S elements. Practical applications Almonds are used as ingredients in a variety of processed foods such as bakery and confectionery products, almond milk, and almond fermented milk. The roasted almond kernels used in desserts, salads, and ice-creams is a popular snack in Turkey. Almonds are considered to be a valuable source of plant proteins in the human diet. Almonds have recognized health benefits, due to high fatty acids, phenolics, and proteins. The most important unsaturated fatty acids of almond oils are oleic and linoleic acids. Phenolic compounds comprise a large and heterogeneous group of secondary plant metabolites distributed widely throughout the plant kingdom.

关键词： Rice bran   Oil body   Microstructure   Stability   Physicochemical characterization  

摘要： Oil bodies (OBs) are a natural delivery system rich in functional ingredients. This study analyzed the structures, physical properties and chemical compositions of rice bran oil bodies (RBOBs) extracted by three different enzymes (Plant exacted enzyme-RBOBP, Xylanase-RBOBX, and their mixture-RBOBM), respectively. The particle size distribution and zeta-potential of RBOBs were determined. The structure of RBOBs was observed by using Cryo-scanning electron microscopy (Cryo-SEM) and confocal laser scanning microscopy (CLSM). RBOBs were also characterized by acrylamide electrophoresis (SDS-PAGE) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) for protein identification. The fatty acid compositions of RBOBs were analyzed by UPLC-Q-Exactive Orbitrap/MS. The three RBOBs exhibited polydispersed size distributions. The RBOBM showed the most uniform distribution due to the highest protein content and strongest steric hindrance. X-ray diffraction (XRD) patterns showed that RBOBs were amorphous structure. SDS-PAGE proved that RBOB surface contained OB related proteins and a large number of extraneous proteins. In addition to the previously known oleosin, some new proteins (germin-like protein 16, osmotin, Histone H4, putative, expressed protein, calmodulin, putative glycopeptide et al.) were identified. The fatty acid composition of RBOB was similar to that of rice bran oil. It was useful to study the natural plant OB delivery system.