我国水-能源-粮食耦合关系及影响因素

为缓解我国水、能源和粮食资源紧张问题，促进资源可持续利用，构建水-能源-粮食系统，利用耦合协调度模型对我国的30个省（自治区、直辖市）进行测算,并利用空间杜宾模型分析主要影响因素。结果表明：2003—2017年，我国能源、粮食评价[JP]指数高于水资源评价指数，系统综合评价指数逐年递增；大部分省份耦合协调度处于初级协调水平且呈现逐年上升的态势，个别省份耦合协调度濒临失调；耦合协调度空间自相关性较强，虽有明显波动，但是呈现逐年加强的态势；影响耦合协调度的主要因素有从业人口数、固定资产投资额、人均生产总值、人口总数、[JP]文盲人口占比、工业污染排放、城镇化。     

Co-precipitation of nano Mg–Y/ZrO2 ternary oxide eutectic system: Effects of calcination temperature

In the family of inorganic nanomaterials, zirconia is a highly promising functional ceramic with a high refractive index, hardness, and dielectric constant, as well as excellent chemical inertness and thermal stability. These properties are enhanced in nano-zirconia ceramics, because nanopowders have a small particle size, good morphology, and uniform and dispersive distribution. In this study, a co-precipitation process was proposed to synthesise highly dispersed MgO–Y₂O₃ co-stabilized ZrO₂ nanopowders. The effects of different calcination temperatures on the crystallisation degree and particle dispersion of zirconia nanopowders were characterised by X-ray diffraction (XRD), thermogravimetry-differential scanning calorimetry (TG-DSC), Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR), nitrogen adsorption using the Brunauer–Emmett–Teller (BET) theory, transmission electron microscopy (TEM), and field emission scanning electron microscopy (FESEM). The optimum synthesis conditions were obtained as follows: 6 h of high-energy planetary grinding and calcination at 800 °C in an electric furnace. Under these optimum conditions, the average particle size of the prepared powder was 28.7 nm. This process enriches the literature on the controllable preparation of Mg–Y/ZrO₂ nanopowders obtained by the co-precipitation method.     

认同度修正下的近相邻改进推荐算法研究

如何融合多方因素准确地为用户提供个性化产品一直是关注的热点问题，由此，一个新的近相邻改进算法融入了大众化认同度和个性化认同度，利于更加高效地挖掘隐藏信息。实验结果表明，相对于传统近相邻算法，认同度修正算法虽然查全率小幅度上下波动，但其他多个评价指标都得到极大提升，假正率和深度有所减少，查准率、[F1]值和提升度得以增加，并且，受试者特征曲线和提升曲线也都说明此修正算法具有更为显著的推荐效果。     

洋葱蛋白及多肽的制备及其体外抗氧化活性评价

对洋葱蛋白、4种不同水解度的粗洋葱多肽、4种分子量范围的纯化多肽组分的水解度、分子量、氨基酸组成、DPPH·清除能力进行了研究。结果表明,洋葱蛋白酶解后分子量大幅降低,必需氨基酸组分和支链氨基酸组分均有所提高,DPPH·清除能力大幅提高,且与水解度成正比;在4种水解度的粗洋葱多肽的纯化组分中,P-III(分子量为1~5kDa)的DPPH·清除能力均为最强,这归功于其合适的分子量分布。该研究为洋葱的高值化利用提供了理论依据。     

改型Wollaston棱镜干涉光谱仪的调制度研究

改型Wollaston棱镜(MWP)无需中继,可构建微型傅里叶变换光谱仪。回顾了MWP的基本原理,从调制度定义出发,计算得到准单色光源的复相干度,找到调制度的影响因素——扩展视场、剪切结构、焦面探测等。建立一般的干涉定域分析模型后,由像点逆光路追迹给出MWP的厚度计算公式,代入调制度约束参数得到不同参量的误差容限。通过FRED记录不同视场扩展情况的灰度与辐照度,结果显示,调制度为0.9时,视场与理论估算值1.24°基本相符;不同剪切量的灰度与辐照度变化特性表明,结构角会使定域垂直系统光轴的入射角发生变化,与晶轴倾角共同影响双折射率差;2.5和8μm像元探测采样表现出调制度差异,描述了定域深度或离焦的影响。以准单色光源、复相干度表示调制度,可将不同影响因素统一至约束参数中,相关变量误差容限可作为MWP-FTS的设计依据。     

高光谱成像检测煎制中调理牛肉品质的变化

将牛肉混合调料后煎制到不同熟度,制成调理肉,研究调理牛肉加工中水分、色泽、嫩度等理化品质及370～1 023nm波段内的光谱特征变化,并构建品质的可视化检测模型。结果表明,牛肉煎制中含水率下降,剪切力上升,且变化显著(P0.05)。由于调料混合以及煎炸加工的不均匀性,调理肉表面色泽与可见光区间光谱变化不规律,而在近红外光谱(800～1 023nm)反射值随熟度显著增高。基于100块牛肉数据,采用主成分分析(PCA)降维高光谱数据,支持向量机(SVM)建模并用粒子群(PSO)优化参数,预测调理牛肉水分和剪切力R~2分别为0.908,0.763,RMSEP分别为1.096,2.097。证实高光谱技术具备对混有各种调料的复杂食品的检测能力。     

Hydrolytic degree and antioxidant activity of purified casein characterised by different haplotypes (αs1-, β- and k-casein) after enzymatic hydrolysis with pepsin and enzymatic extract from Pleurotus eryngii

The aim of this study was to estimate the hydrolytic degree and antioxidant activity of purified casein characterised by different haplotypes (α_s1-, β- and k-casein) after in vitro digestion with two different enzymatic systems: pepsin from porcine gastric mucosa (EP) and a crude enzymatic extract from the edible mushroom Pleurotus eryngii. The used enzymes showed a different mode of casein catalysis with a consequent production of peptides of different antioxidant activity. The CN haplotype significantly influenced peptides production; in fact, the amino acid substitutions caused by genetic polymorphisms at the α_s1-, β- and k-CN loci influenced the sites of enzymatic cleavage and therefore the produced peptides. The above is evidenced by the different antioxidant activity found in the hydrolysates depending on the used enzymatic system, the CN haplotype, and the CN haplotype × enzymatic treatment interaction. The findings of this study are a perspective for the production of specific foods that exert a biological effect in addition to the nutritional one.     

某矿山充填料浆坍落度试验研究

充填采矿成为了目前的发展趋势,充填料浆的流动性在此过程中的作用不容小觑。对某矿山的料浆流动性进行坍落度试验研究。结果表明,塌落度随着充填料浆的灰砂比和料浆浓度的变化而变化,当料浆的浓度小于74%时,坍落度大于22.5 cm,其流动性明显有所改观,此时可实现管道自流输送的目的。低浓度的充填料浆有较好的流动性,但该情况下的充填体强度不能得到很好的保障,通过观察充填料浆在不同灰砂比下不同浓度的坍落度以及摊开的样子得出,浓度在68%之上的料浆具有良好的保水性,不会有粒级不同的颗粒相互分离或析水的不良情况,因此把充填料浆的浓度初设为68%~74%。相应的坍落度为22.5cm,完全摊开。