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关键词： High-moisture extrusion   Barrel temperature   Soy protein isolate   Pea protein isolate   Fibrous structure  

摘要： This study aimed to compare the physicochemical properties of high-moisture extrudates prepared from soy protein isolate (SPI) and pea protein isolate (PPI) at different barrel temperatures (BTs) of 120 degrees C, 140 degrees C, and 160 degrees C. Increasing BT promoted more anisotropic structures and darker extrudates. PPI extrudates produced more fibrous structures than SPI extrudates under the same BT. Textural and rheological properties of SPI extrudates elevated significantly with increasing BT. Compared to SPI extrudates at the same BT, PPI extrudates displayed apparently weaker shear thinning (gel-like) behavior and showed less textural properties of hardness, chewiness, and tensile strength. PPI extrudates showed no significant differences in hardness and chewiness to the cooked chicken breast. Heat-treatment during low-field nuclear magnetic resonance (LF-NMR) measurements promoted the release of intra-space water of the fibrous structure for both SPI and PPI extrudates. Water in PPI extrudates was more prone to migrate compared to SPI extrudates. Hydrogen bonds and hydrophobic interactions played marginally more essential roles than the disulfide bonds to stabilize protein structure for both SPI and PPI extrudates. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) showed that most protein subunits were still present after extrusion, except two bands over 100 kDa in SPI extrudates extracted by phosphates buffer. This study provided valuable information for improving the quality of high moisture extrudates based on SPI and PPI.

关键词： Norway spruce bark   Bio-based carbon porous materials   Different chemical activation   Ultrafast acetaminophen removal   Pore-filling mechanism of adsorption  

摘要： Preparing sustainable and highly efficient biomass-based carbon materials (BBPM) as adsorbents remains a challenge for organic pollutant management. In this work, novel biobased carbon material has been synthesized via facile, sustainable, and different single-step pyrolysis chemical methods (KOH, ZnCl2, ZnSO4, and MgCl2) using a Norway spruce bark as suitable and efficient carbon precursor. The effects of each chemical activator on the physicochemical structure of synthesized were thoroughly investigated as well as its performance on the acetaminophen adsorption. The results showed that the use of different chemical activation provoked remarkable differences in the BBPM physicochemical characteristics. The KOH activation generated material with the highest specific surface area (2209 m(2) g(-1)), followed by ZnCl2 (1019 m(2) g(-1)), ZnSO4 (446 m(2) g(-1)), and MgCl2 (98 mm(2) g(-1)). The chemical characterization of the carbon materials indicated that the activation of MgCl2 yielded a material around three times more hydrophobic when compared with the other activation methods. The acetaminophen removal showed to be ultrafast, not only due to the BBPM's microstructure but also to the abundant active sites provided by the different chemical activation methods. The adsorption equilibrium times were reached at 1 min for BBPM-KOH and BBPM-MgCl2 and 15 min for BBPM-ZnSO4 and BBPM-ZnCl2. The adsorption process suggests that the pore-filling mechanism mainly dominates the acetaminophen removal but also some physical-chemical interactions such as hydrogen bonding between the amide group of acetaminophen and oxygenated or nitrogenated groups of biochar, 7C-7C interactions between the aromatic ring of the pharmaceutical and the aromatics of biochar, n-7C interaction, van der Waals interactions. The BBPM regeneration studies showed very good cyclability;in the 3rd cycle, the removal was approximately 70% for all four samples. The samples were also used to treat two synthetic e

关键词： 物理化学   3,4-二硝基吡唑   DNP   2,4-二硝基苯甲醚   DNAN   熔铸炸药   载体炸药  

摘要： 为了对比载体炸药3,4-二硝基吡唑(DNP)和2,4-二硝基苯甲醚(DNAN)以及以其为基的熔铸炸药的性能,制备了不同载体的DNP基熔铸炸药和DNAN基熔铸炸药,系统研究了两种炸药的凝固特性、流变特性、安全性、能量以及力学性能。结果表明,载体炸药DNP和DNAN药柱内部形成的缩松缺陷均似漏斗状,DNP凝固过程中释放的结晶潜热小于DNAN;DNP基熔铸炸药的表观黏度大于DNAN基熔铸炸药的表观黏度;DNP基熔铸炸药的摩擦感度和撞击感度与DNAN基熔铸炸药相当,在强约束条件下两种混合炸药的慢速烤燃试验均发生爆炸反应;DNP基熔铸炸药和DNAN基熔铸炸药的爆速分别为8301m/s和7856m/s,爆压分别为29.6GPa和25.1GPa,格尼系数理论计算值分别为2.84和2.76mm/μs;DNP基熔铸炸药的抗压强度与DNAN基熔铸炸药相当,但前者的抗拉强度优于后者。得出在安全性基本相当的情况下,DNP基熔铸炸药的能量和力学性能优于DNAN基熔铸炸药。

关键词： 物理化学   高聚物黏结炸药   PBX   氟聚物黏结剂   TATB   造型粉可压性  

摘要： 为了探究氟聚物黏结剂对高聚物黏结炸药(PBX)造型粉可压性的影响,对3种不同黏结剂(F2311、F2313、F2314)的TATB基PBX造型粉进行压制成型试验,获得了PBX造型粉的压缩位移曲线;采用排水法和小角X射线散射技术(SAXS),得到了PBX成型样品的密度和孔隙率随温度的变化规律。结果表明,3种造型粉在载荷最大时的压缩位移与松装密度有关,松装密度越大,造型粉的压缩位移越小;PBX成型样品的密度和孔隙率均会在某个压制温度发生突变,TATB/F2311、TATB/F2313和TATB/F2314密度突变的温度分别为60、80和100℃;3种PBX成型样品的孔隙在3~5nm和30~50nm两个区域呈双峰分布,当压制温度高于突变温度时,40~50nm的孔隙明显降低。此外,建立了修正比能量可压性评价方法,对3种造型粉进行了可压性评价,获得的可压性系数与相对密度相关系数较好(0.9以上),验证了该方法的合理性和有效性。相同压制条件下,以F2311为黏结剂的TATB基PBX造型粉的可压性系数最大,可压性最好。

关键词： 胶体化学   物理化学   课程改革   启发式方法   自主学习  

摘要： 本文以长江大学石油工程专业大二某班为试点,以胶体系统为例针对应用导向的石油工程物理化学课程改革进行了初步探索与实践。笔者通过启发式教学方法引导学生思考、探索和自主学习的方式开展了“教师引导,学生主体”的教学模式,努力做到让学生想“动”、会“动”,能“动”,培养学生自主发现规律,自主寻找方法,自主探索思路、自主解决问题的能力。同时基于此次实践存在的问题提出了优化时间安排、优化督促机制和及时更新教学理论等改进方法。

关键词： 物理化学   教学改革   课程思政  

摘要： 《物理化学》是化学与化工类各专业本科学生的基础课程。为了进一步提升本科生《物理化学》课程教学的质量,本文针对我校本科生《物理化学》课程教学过程中存在的部分问题进行了分析。结合当前教育形式多元化的大环境,重点提出了将课程思政融入教学内容,并且充分利用网络教学形式的优点对《物理化学》课程的教学模式改革进行了探讨。为高校教学改革提供新思路。

关键词： 物理化学   学习成果为导向   混合式教学模式  

摘要： 根据OBE理念,探讨“以成果为导向,以学生为中心”的物理化学线上线下混合式教学模式的构建与实践。从教学目标、教学方法、教学设计、教学内容和教学考核等方面综合实施教学改革,积极构建新型的物理化学教学模式。实践表明,该教学模式能够激发学生的学习兴趣和学习潜能,有效培养学生自主学习能力和创新能力,提高学生分析问题和解决问题的综合运用能力,提高物理化学的教学质量。

关键词： 中药专业   物理化学   课程思政  

摘要： 物理化学是中药专业重要的专业基础课,物理化学各章节的内容,都与中药学专业课有千丝万缕的联系,物理化学已渗透到中药学专业各门课程中,物理化学的学习将对中药学专业的学习和研究起到重大的指导作用[1]。在物理化学教学中,努力发掘思政元素,将专业知识教育与思政教育有机结合,引导学生树立正确的人生观、价值观、世界观,培养学生成为合格的中医药人才,最终实现“立德树人”的根本任务。

关键词： OBE理念   药学类   物理化学实验课程改革  

摘要： 针对目前我校药学类专业物理化学实验教学存在的现状,文章基于OBE理念的“以成果为导向,持续改进 的”原则,从课程目标、教学模式和评价机制三个方面对物理化学实验课程进行课程改革探析,能够取得良好的学习效 果,培养出高素质专业化的医药类应用型人才。

关键词： 人教版教材   高考化学试题   活化分子   活化能   《化学反应原理》   物理化学   实验温度范围   平均能量  

摘要： 2019年人教版教材选择性必修1《化学反应原理》中指出“活化分子具有的平均能量与反应物分子具有的平均能量之差,叫作反应的活化能”.傅献彩等编著的《物理化学·下册》指出根据Arrhenius经验式,E_(a)看作是与温度无关的常数……,实验温度范围适当放宽或对于较复杂的反应.