响应面优化人参果铁皮石斛花复合果酒生产工艺

为提高人参果与铁皮石斛花的经济附加值、丰富果酒产品的种类,以人参果与铁皮石斛花为主要原料,进行复合果酒的研制。通过单因素试验、响应面设计优化人参果铁皮石斛花复合果酒的生产工艺条件。结果表明,在鲜榨的人参果汁中添加7%铁皮石斛花,调整初始糖度为22%,接入0.04%酿酒酵母,于20℃条件下发酵7 d可获得浅黄透明、酒香和谐、滋味爽口的复合果酒,其感官评分、酒精度、黄酮类物质含量分别为90.1、12.5%vol、168.1μg/mL。

四种石斛花化学成分及抗氧化活性

为进一步挖掘石斛花的食用及药用价值,测定比较铁皮石斛花(D.officinale Kimura et Migo’s flower, DOF)、紫皮石斛花(D.devonianum Paxt’s flower, DDF)、鼓槌石斛花(D.chrysotoxum Lindl’s flower, DCF)及梳唇石斛花(D.strongylanthum Rchb. f.’s flower, DSF)的生化成分、功能性成分及抗氧化活性。结果表明:四类石斛花中多酚(polyphenols, PP)、游离氨基酸(free amino acids, FAA)、多糖(polysaccharides, PS)、可溶性糖(soluble sugars, SS)的含量以及氨基酸总量、类黄酮物质总量分别为6.28%~14.58%、0.94%~2.37%、1.47%~5.73%、46.85%~53.46%、3.07~8.95 mg/g、0.43~5.87 mg/g,其中,PP、FAA、PS的含量在DOF中最高,SS的含量在DCF中最高,氨基酸总量在DSF中最高,类黄酮物质总量在DDF中最高。DSF的总抗氧化能力(total antioxidant capacity, T-AOC)最强,DDF对DPPH·及·OH清除能力最强,其半抑制浓度(IC_(50))分别为0.054 1 mg/mL和0.509 2 mg/mL。此外,相关分析发现PP、FAA、芦丁、天冬氨酸、谷氨酸、丝氨酸、组氨酸、甘氨酸、苏氨酸、精氨酸、丙氨酸、酪氨酸、半胱氨酸、甲硫氨酸、苯丙氨酸、异亮氨酸、亮氨酸与抗氧化活性正相关(P<0.01)。可见,研究结果可为石斛花相关健康产品、日化产品等的研究开发提供一定基础。

翻转课堂教学模式在舟桥工程课程大班教学改革中的应用研究

从课程教学改革目标出发,围绕学生人数较多的大班教学过程中需要解决的问题,开展翻转课堂教学模式在舟桥工程课程教学改革中的应用研究,并创新研究课程考核机制。研究成果可为新的教学模式在军队院校专业课程教学中的应用,提供理论和实践依据。

基于有限元方法的舟桥接头疲劳寿命分析

以某型舟桥单双耳接头为研究对象,通过Inventor构建三维实体模型,并利用ANSYS Workbench进行静力学计算,采用E-N分析方法对单双耳接头进行疲劳寿命求解,而后得到了荷载水平对疲劳寿命的影响。获得的仿真结果与设计指标进行对比,表明其可以有效预测疲劳寿命。为舟桥装备的寿命预测提供依据与方法。

《渡河装备原理与运用》课程教学内容改革与模式研究

根据新制定的教学大纲,针对道路桥梁与渡河工程专业《渡河装备原理与运用》课程,从课程教学改革目标出发,以提高学员装备操作技能和组织训练能力为核心,重构课程教学内容体系,开展课程教学模式设计,优化课程组织实施过程。研究成果可为军队院校装备课程教学改革与实施提供理论和实践依据。

WAVE DIFFRACTION ON ARC-SHAPED BOTTOM-MOUNTED BREAKWATERS

An analytical method was developed to study the wave diffraction effects on arc-shaped bottom-mounted breakwaters. The breakwater was assumed to be rigid, thin, impermeable and vertically located in water of constant depth. The fluid domain was divided into two regions by imaginary cylindrical interface. The velocity potential in each region was expanded with cigcnfunctions. By satisfying continuity of pressure and normal velocity across the imaginary fluid interface, a set of linear algebraic equations could be obtained to determine the unknown coefficients for eigenfunction expansions. The accuracy of the present model was verified by a comparison with existing results for the case of an isolated straight-line breakwater. Numerical results, in the form of contour maps of the non-dimensional wave amplitude around the breakwater and diffracted wave amplitude at three typical sections, were presented for a range of wave parameters. Results show the arc-shaped bottom-mounted breakwater is generally effective in defending against waves. The wave amplitudes at most sheltered areas are commonly 10%-50% of incident wave amplitudes under most wave conditions.

ANALYTICAL RESEARCH ON THE WAVE DIFFRACTION OF ARC-SHAPED FLOATING BREAKWATERS

An analytical method was developed to study the wave diffraction on are-shaped floating breakwaters. The floating breakwater was assumed to be rigid, thin, vertical, immovable and located in water of constant depth. The fluid domain was divided into two regions by imaginary interface, The velocity potential in each region is expanded by eigenfunctions. By satisfying continuity of pressure and normal velocity across the imaginary fluid interface, a set of linear algebraic equations could be obtained to determine the unknown coefficients for eigenfunctions. The accuracy of present model and the computer program were verified by a comparison with ex isting results for the case of arc-shaped bottom-mounted breakwaters. Numerical results, in the form of contour maps of the non-dimension wave amplitude around the breakwater, were presented for a range of wave and breakwater parame ters. Results show the wave diffraction on the arc-shaped floating breakwater is related to the incident wavelength and the draft of the breakwater.