不同干燥处理对马齿苋总酚含量及其抗氧化性的影响

分别采用热风干燥法、真空微波干燥法和真空冷冻干燥法处理马齿苋,测定马齿苋粉甲醇提取液的总酚含量、总抗氧化能力、还原能力、DPPH·清除能力、羟自由基清除能力和超氧阴离子自由基清除能力,研究不同干燥方法对马齿苋粉总酚含量和抗氧化性的影响。结果表明,真空冷冻干燥法制得的马齿苋干粉样品中总酚含量显著高于真空微波与热风干燥样品;不同的干燥方法对马齿苋粉的抗氧化性有明显影响,真空冷冻干燥法制得的马齿苋粉甲醇提取液的总抗氧化能力、还原能力、DPPH·与羟自由基清除能力显著高于真空微波和热风干燥法制得的马齿苋粉(P0.05),但真空冷冻干燥样品与真空微波干燥样品对O_2~-·的清除率无显著差异,综合考虑产品品质与加工成本,采用真空微波干燥法更为合理。     

不同干燥方式制备菠萝粉的效果比较

对热风干燥、真空干燥、微波真空干燥、真空冷冻干燥、喷雾干燥5种干燥方法生产的菠萝粉的VC含量和总胡萝卜素的保留率、流动性、润湿性等分别进行比较。研究发现,微波真空干燥方法生产的菠萝粉的品质明显好于热风及真空干燥的产品,接近真空冷冻干燥的产品,喷雾干燥产品的多项指标居中。     

干燥方式对萌动苦荞品质的影响

研究了热风干燥、微波干燥、挤压膨化干燥和真空冷冻干燥4种干燥方式对萌动苦荞色泽、多酚含量、总黄酮含量和复水率的影响。结果表明,在真空冷冻干燥条件下,萌动苦荞的麦芽颜色变化最小;热风70℃干燥时复水率最低;不同干燥方法对萌动苦荞中的黄酮含量均有影响,微波高火干燥样品中总黄酮的含量明显高于其他干燥方法。为萌动苦荞的深加工提供理论依据,具有一定的理论和实践价值。     

叶菜类蔬菜粉的加工研究

采用热风干燥和真空干燥制备蔬菜粉(青菜粉和芹菜粉),对2种干燥方法、制粉工艺流程、干燥温度及制得的蔬菜粉冲调稳定性等进行研究。结果表明,对样品进行切分,热风干燥温度为60℃,粉粒直径≤0.125μm时,制得的蔬菜粉的颜色和冲调稳定性最好。     

微波真空干燥大蒜片的研究

利用微波真空干燥大蒜片使其水分降至7％左右，测试数据表明，用微波真空干燥所得的大蒜片的质量与冷冻干燥产品的质量非常接近，比传统的热风干燥(60℃)产品质量好得多。     

不同干燥方式对南瓜粉品质的影响

以南瓜为材料,采用热风干燥、微波干燥、真空干燥3种方式进行干燥、粉粹,研究干燥方式对南瓜粉品质的影响。结果表明,热风干燥的总酚含量最高,β-胡萝卜素含量、溶解性、复水性最低;微波干燥的b~*值、容重、溶解性、复水性、持水性、持油性最高,L~*值、a~*值、VC含量最低;真空干燥的L~*值、a~*值、VC含量、β-胡萝卜素含量最高,总酚含量、容重、溶解性、持水力、持油性最低。为了确保南瓜粉的营养品质,同时考虑南瓜粉的外观品质,制备南瓜粉的干燥方式以真空干燥为最佳。     

真空冷冻和热风干燥对哈密瓜片品质的影响

以西州蜜17号为原料,采用热风干燥和真空冷冻干燥方式对哈密瓜片进行干燥,研究不同干燥方式对哈密瓜片营养成分、色泽、微观结构以及香气成分的影响。结果表明,不同干燥方式对哈密瓜片的营养成分、色泽、微观结构以及香气成分均有显著影响。两种干燥方式中,真空冷冻干燥产品的色泽优于热风干燥;总酚、总黄酮含量以真空冷冻干燥产品最高,总糖、VC含量以热风干燥产品最高,真空冷冻干燥和热风干燥能显著降低不同营养成分的损失;热风干燥产品的微观整体结构更加塌陷,而真空冷冻干燥产品出现了孔洞结构;不同干燥方式处理哈密瓜片的香气物质、种类及相对含量具有一定差异;热风干燥主要的香气成分中,酮类中的香叶基丙酮含量最高,为19.47%,真空冷冻干燥主要的香气成分中,酮类中的β-紫罗酮含量最高,为26.12%。综合考虑加工成本与产品品质,采用热风干燥更适合哈密瓜片的加工生产。     

不同干燥方式对十香菜根多酚和黄酮含量及其抗氧化活性的影响

对十香菜根分别进行自然风干、热风干燥、真空干燥、微波干燥、真空冷冻干燥处理,并对其总酚与总黄酮含量及抗氧化活性进行测定,研究不同干燥方式对十香菜根的影响。结果表明,真空冷冻干燥处理后十香菜根具有较高的功能性成分和抗氧化能力,多酚含量为6.672%,黄酮含量为4.784%,DPPH·清除率为60.081%,羟基自由基清除率为25.958%,ABTS+·清除率为66.148%,可作为干燥十香菜根的合适方法。     

干燥方法对南瓜粉营养物质和抗氧化性的影响

以南瓜为原料,考察冷冻干燥、真空干燥、热风干燥等干燥处理前后南瓜粉中多糖含量、可溶性膳食纤维含量、可溶性蛋白含量、β-胡萝卜素含量、羟基自由基清除率的变化。结果表明,冷冻干燥后南瓜粉中多糖、β-胡萝卜素、可溶性蛋白质含量及羟基自由基清除率最高,与新鲜样品相当;南瓜粉对羟基自由基的清除效果与南瓜粉中的多糖含量、β-胡萝卜素的含量呈线性相关性。     

香蕉片真空冷冻干燥工艺研究

以产品复水率、色差值、含水量和VC含量为指标,采用液氮快速冻结与真空干燥结合技术,对比热风干燥加工方式,进行了香蕉片的真空冷冻干燥研究;着重探讨了工艺参数(物料厚度、搁板温度和真空度)对真空冷冻干燥时间的影响,同时绘制出不同冻结速率下香蕉片的冻结曲线。试验结果表明,从缩短真空冷冻干燥时间和保证产品品质的角度考虑,较优的香蕉片真空冷冻干燥工艺条件为:物料厚度6～8mm,搁板温度43～47.5℃,真空度50～60Pa。     

冷冻干燥速溶蛋花汤的加工技术

介绍了运用冷冻干燥技术进行速溶蛋花汤的加工,研究了生产工艺、特点以及影响产品质量的主要因素。试验表明,采用冷冻干燥技术加工的速溶蛋花汤,具有营养丰富、风味独特、方便快捷等特点。     

Measuring of Quantity of Matter-mass and the Measuring of Inertia of Matter-momentclm

A new definition of inertia,i.e. the momentum is the measuring of inertia of matter, is proposed. The article through and etc., subjects, the correctness of the new notion of inertia:The monentum is the measuring of inertia has been demonstrated, and the unsolved contradictions of the traditional definition of inetia. And the mass is the measuring of inertia has been revealed.     

香蕉遗传转化方法研究进展

香蕉是热带亚热带发展中国家重要的粮食作物和碳水化合物来源。但近年来,香蕉生产受到严重的病虫危害。大多数香蕉栽培品种是三倍体,生长周期长,而且不孕。由于没有种子,给繁殖和育种带来一定的困难。遗传转化技术的发展为香蕉品种的改良提供了一种有效的手段。香蕉的遗传转化方法有电激法、基因枪法、农杆菌介导法等。农杆菌介导法的应用是香蕉品种改良的一个重大突破。香蕉遗传转化的外植体也发展到多种,有原生质体,胚性细胞悬浮系,分生组织,以及横切薄片等。近几年,随着分子生物学的发展,出现了转化效率更高,重复性更好的香蕉遗传转化技术。如农杆菌和基因枪结合法,离心辅助农杆菌介导法、真空渗透技术等。这些新技术新方法的出现,必将推动香蕉产业高速发展。     

壳聚糖对石榴果汁澄清效果的影响

利用壳聚糖的絮凝作用对壳聚糖在甜石榴汁澄清中的应用效果进行了研究,试验结果表明,壳聚糖用量为0.3g/L、澄清时间为60min、温度为35℃时,甜石榴汁透光率可达85%以上,且通过对壳聚糖处理前后可溶性固形物、总酸、VC等营养成分含量的比较,确定以上工艺参数为甜石榴汁澄清的最佳选择。     

新疆布尔津县土地利用格局特征研究

基于RS与GIS技术,利用景观生态学理论及景观格局指数对布尔津县土地利用现状进行定量分析。结果显示为：（1）布尔津县以草地、林地为主要景观类型,镶嵌着耕地、水域等景观类型。（2）四个分区（即高山区、丘陵区、平原区、荒漠区）的林地资源组成差异明显,耕地、居民、交通及工矿用地集中分布在丘陵区和平原区（3）从各项指数来看,高山区的多样性指数较低;平原区是受人文因素最多的区域,景观优势度低,各种土地利用类型比例差异不大,有利于生态可持续发展,但要合理的开发利用;荒漠区生态环境相对脆弱,要加强生态环境的保护与改善。通过该研究对布尔津县的土地利用现状作一个了解,为该县乃至整个地区的景观规划和可持续发展战略提供科学依据。     

酸枣幼根原生质体的制备

以生长6～9 d的酸枣种子幼根为试验材料,0.7 mol·L-1甘露醇作为渗透压稳定剂、pH值5.5～6.0、28℃恒温水浴条件下,以光学显微镜观察的水解总时间、初始产生原生质体的时间、原生质体产量及细胞碎片量为指标,研究通过酶水解来制备酸枣幼根原生质体的方法.结果表明,在含1％果胶酶+4％纤维素酶R-10+3％纤维素...     

影响核桃贮藏品质因素的分析

介绍了几种核桃贮藏方法,综述了影响核桃贮藏品质的几个主要因素,以及针对上述影响因素提出若干解决对策.     

The Simulation of Comfort of Nine DOF of Automobile

Automobile comfort dynamic simulation is necessary when we predict and evaluate the comfort of a automobile or optimize performance of automobile. The nine DOF vibration model of automobile is established , which acts root mean square value of body in multiple work conditions as comfort evaluation indices. Based on the comfort simulation, the Hongyan 1160 is predicted in the way of comfort. The programmes can be used in many different automobiles . The computational result indicates that the model can simulate vibration of automobile truly. It is significant to research automobile comfort evaluation to optimize performance of automobile and comfort simulation .The computational program can be applied to optimize or simulate which has some reference value.     

Efficiency of water use of early plantings of sunflower

Rain fed crop production in Mediterranean environments depends to a large extent on strategies that avoid the intense summer drought. Early plantings of sunflower have given consistently higher yields in such environments, but the basis for such yield increases has not been explored. We conducted two field experiments at Cordoba (Spain) to investigate the effects of an early and a late planting date on the components of water-limited crop productivity; namely, water use (T), water use efficiency (TE) and harvest index (HI) of sunflower. The results were generalized by simulating rain fed sunflower yields, under early (1 January) and late (15 March) plantings, for a 25-year period with the aid of a simulation model of the Ceres type (OILCROP-SUN) which has been validated in Cordoba. Experimental seed yields of early plantings in 1989 and 1996 were 2.0 and 3.0 t ha⁻¹, while late plantings yields were 1.3 and 2.4 t ha⁻¹, for the 2 years. Average simulated yields were 2.7 ± 1.1 and 1.9 ± 0.7 t ha⁻¹ for early and late plantings, respectively. For the 2 years, T of early plantings was higher than that of late plantings, but the response of TE and HI to planting date was not the same in the two experiments. In the simulation exercise, T and TE of early plantings were consistently higher than those of late plantings, while there were no differences in the HI for the two planting dates. We conclude that early plantings of sunflower increase rain fed yields by increasing both T and TE, while the impact of planting date on HI very much depends on the crop water stress pattern, which is quite variable from year to year even in the predictable Mediterranean environment.     

Establishment of High-frequency Regeneration System of Explants of Alfalfa

The cotyledon and hypocotyl of eight varieties of alfalfa( Medicago sativa L. )are used to study the effect of different cultivation procedures and genotypes on embryogenic callus and embryoid induction,plant development and transplant of alfalfa.The varieties of alfalfa with high embryoid induction rate and high differentiation rate are screened. A high frequency regeneration system for alfalfa tissue culture is established:which is benifical to the gene transformation of alfalfa.