硼对第二代镍基单晶高温合金显微组织的影响

硼（B）是强化镍基单晶合金小角度晶界的重要微量元素，但目前关于B对镍基单晶合金显微组织影响的系统报道非常有限。通过对3种不同B含量（质量分数分别为0、0.01%、0.02%）的第二代镍基单晶合金DD11铸态及热处理态组织定量表征，研究了B对相转变温度、（γ+γ''）共晶组织、硼化物的影响。结果表明：B显著降低合金的固液相线，提高铸态共晶组织体积分数；0.01% B的加入，合金中未出现M₃B₂型硼化物相；而0.02% B的加入，显著促进了骨架状硼化物的形成，降低合金初熔点，引起残余共晶含量的大幅度提高；骨架状硼化物吸收较多的Cr、Mo和W等元素，降低合金的固溶强化效果，可导致单晶合金基体的蠕变性能大幅度降低。研究结果对认识单晶合金中微量元素B的作用机理及优化B成分范围具有理论指导意义。     

空间高度对球面网壳结构内爆炸响应的影响

基于修正后的Johnson-Cook材料模型，应用ANSYS/LS-DYNA建立K8型单层球面网壳计算模型，对内爆炸下不同空间高度的结构爆炸响应进行计算和分析。首先，分析结构内爆炸冲击波传播规律，验证模型参数选取的可行性；其次，讨论内爆炸作用下球面网壳的动力响应，对比分析不同本构模型对爆炸响应的影响；最后，定义下部支承结构所围体积占结构所围总体积的比值为空间高度系数，讨论空间高度系数对墙面未开洞和墙面开洞球面网壳动力响应的影响。结果表明，爆炸冲击波在球面网壳结构角部有汇聚效应，与反射冲击波共同作用，严重影响球面网壳结构的动力响应；对于墙面未开洞的球面网壳，爆炸响应受反射冲击波影响较大；对于墙面开洞的球面网壳，爆炸响应受空间高度系数影响较大。基于研究结果给出了球面网壳结构在内爆炸下防爆和抗爆设计的合理空间高度系数建议值。     

蛋壳壳膜分离技术的研究

蛋壳主要由石灰质真壳和壳下膜2个部分组成,石灰质真壳中含有大量碳酸钙,是一种天然绿色的钙源;壳下膜中含有N-乙酰氨基葡萄糖半乳糖硫酸软骨素、氨基酸等多种可溶性高分子化合物。如何能采取方法对壳膜进行有效分离,使其物尽其用,可以充分挖掘蛋壳中潜在的利用价值,还可以从源头上减少垃圾排放量,有利于保护赖以生存的生态环境。通过介绍目前国内外3种壳膜分离的方法,阐述了每种方法的优缺点,为有效利用蛋壳壳膜资源提供了科学依据。     

棉铃发育过程中不同组织IAA含量变化特点

为了解IAA与棉纤维品质形成间的关系及棉铃各部位IAA积累转运特点,本研究分析了棉铃各部分在发育过程中IAA含量的变化特点。通过选择陆地棉标准系TM-1、长纤维种质‘母35’和短纤维种质‘208’3个纤维长度差异较大的陆地棉材料,利用酶联免疫法对浙江杭州、海南三亚两地田间试验的各材料不同发育阶段的棉仁、棉籽壳、棉纤维、棉铃壳进行了IAA含量的测定。结果表明,不同参试材料的棉仁IAA含量存在明显差异,棉籽壳、棉纤维与棉铃壳的IAA含量峰值出现时间晚于棉仁,棉铃各个组织IAA含量具有随棉铃组织从内向外逐渐降低的趋势。研究表明,IAA可能是棉纤维发育的正效应因子,且棉铃发育过程中IAA可能呈初期在棉仁富集、随发育进程沿棉铃组织由内向外运输的规律。     

三个复粒水稻材料的复粒频率及其复芽率

对3个复粒水稻材料的复粒频率和复芽率进行了研究。粳型CDR-2的复茅率和芽基数增加率显著高于籼型CDR-1和CDR-3;CDR-1在剥去颖壳下催芽,复芽率和芽基数增加率明显提高。     

干旱胁迫对小麦主要器官干物重的影响

以7个小麦品种为试验材料,研究其主要器官干物质在干旱胁迫条件下发生的相应变化。结果表明,穗粒重受影响最小,依次为颖壳质量、茎秆干质量和叶片干质量。叶片和颖壳在干物质积累上收支平衡,茎秆是籽粒干物质积累的部分来源。     

中棉所29不同部位棉铃干物质积累动态研究

以抗虫杂交棉中棉所29为材料、33B为对照,设早、中、晚三个播期,分上、中、下三个部位,对铃壳及子棉的干物质积累动态分别进行了研究。结果表明,中棉所29在铃壳营养物质的再分配及子棉干重积累方面具有明显的杂种优势。不同播期结果表现为:在适期早播情况下,利于中棉所29棉铃铃壳中的干物质向子棉中转移,以提高其单铃重;中部棉铃铃壳干物质转移率和子棉的干物质积累量明显高于下部和上部果枝棉铃。     

中子仪测定土壤水分方法的研究进展

中子仪测定土壤水分方法的核心内容是中子计数与土壤含水量的曲线标定,为了绘制精确的能够应用于不同土壤层次、土壤质地、土壤有机质含量和土壤剖面含水量变化等条件的标定曲线,通过对已取得的不同土壤条件下标定曲线文献的整理分析,从中子仪测水的工作原理出发,分析了影响中子仪测定土壤水分的主要因素,概括了测水所遇到的主要问题及其解决的方法,并对准确测定含水量层状变化土壤,提出标定曲线绘制的可行方法。根据中子计数值不仅与土壤容积含水量有关,而且还与水分和中子计数器的距离有关,提出了进一步准确标定曲线的研究方法。     

食品加工剩余物板栗壳的利用研究进展

为了更好地对食品加工剩余物板栗壳进行开发利用,促进节能减排,综述了国内外最近20年在板栗壳资源化利用方面的研究进展,发现现有研究涉及将板栗壳作为生物吸附剂用于重金属污水处理、作为基质用于食用菌栽培和作为原料用于活性炭制备,以及从中提取天然色素用于食品着色和纺织品印染等方面,但这些研究并不系统,今后还需对板栗壳色素进行安全性评价,补充其毒理学和代谢方面的数据。板栗壳对重金属的吸附量偏低,有待于进一步通过理化改性提高其吸附性能,提取过色素的板栗壳残渣可进一步作为原料用于制备活性炭,以达到循环利用。     

不同剂量中子辐射针叶豌豆的M1代效应研究

研究不同中子吸收剂量对豌豆产生的M1代生物学效应,为放射生物学研究和中子辐射诱变育种提供重要参考。本研究用²⁵²Cf源发射的中子对针叶豌豆(Pisum sativum L. var MZ-1)的干种子进行了辐射,研究了M1代豌豆生长过程中形态和生理方面的生物学效应。结果表明：中子辐射(0.24~4.33 Gy)对M1代豌豆的萌发能力和幼根的生长均有一定的促进作用,低吸收剂量的中子辐射(0.38 Gy)能够显著促进豌豆的萌发和幼根的生长,较高中子吸收剂量(1.66、4.33 Gy)的辐射对M1代豌豆苗期株高的生长有抑制作用,较低中子吸收剂量(0.24、0.38、0.84 Gy)的辐射对M1代豌豆苗期株高的生长有促进作用。微剂量(0.24、0.38 Gy)的中子辐射不会引起M1代豌豆的形态变异,中子吸收剂量在0.84~4.33 Gy间,可以引起M1代豌豆分枝致变。以上结果说明,0.24~4.33 Gy的低吸收剂量的中子辐射豌豆干种子能够使M1代豌豆产生生物学效应,且有比较明显的规律,可以用于辐射育种研究。     

Effect of surface defects on anodic oxidation coating of7075 aluminum alloy

The interface interaction between geogrid and soil is one of the key issues on geosynthetic reinforced soil structures. Comparative analysis of properties of geogrid clay interface under the different normal stresses and water contents of clay were conducted by medium sized pullout tests. The results show that ultimate pullout force of geogrid, interfacial cohesion and frictional coefficient are significantly affected by water content of clay. Ultimate pullout force of geogrid tends to be remarkably different when subjecting to different normal stresses at a lower water content. And frictional coefficient of interface decreases with the increase of water content, and interfacial cohesion has a tendency to increase followed by decrease with the increase of water content. Moreover, aforementioned three parameters can keep constant when water content is close to value at plasticity limit. The curves of load and displacement possess three stages: linear increase, non linear increase and ultimate pullout. As water content increases, the interval nonlinear changing stage is not conspicuous. Furthermore, it is found that geogrid strains in transversal ribs tend to increase but to reduce in longitudinal ribs when last level load is kept for given hours and then followed by unloading pullout force.     

Effect of Yttrium on Morphologies of Precipitation Phases Along Grain Boundary of As-cast ZK60 Magnesium Alloy

Morphologies of precipitation phases along grain boundary of the as-cast Mg-6.0Zn-0.45Zr, Mg-6.0Zn-(1.2Y) and Mg-6.0Zn-0.6Zr-1.0Y alloys are studied by using the methodologies of metallurgical phase analysis, scanning electron microscopy(SEM) analysis and energy diffraction x-ray(EDX) analysis. The experimental result indicates that the main precipitation phases along grain boundary of the as-cast alloys Mg-6.0Zn-0.45Zr is Mg-Zn binary phase. There are two kinds of precipitation phases along grain boundary for Mg-6.0Zn-1.2Y and Mg-6.0Zn-(0.6)Zr-1.0Y alloys. One grew at triangular grain boundary, which is fish-bone -like and contained Mg-Zn binary phase and Mg-Zn-Y ternary phase. The other distributed mainly around the grain, which is net-like and contained Mg-Zn-Y ternary phase. In addition, there are lots of granular phases, extending to the interior of the grain, at the rim of grain boundary phases. Finally, Y can intensively change morphology of precipitation phases along grain boundary of the as-cast Mg-Zn-Zr alloy (ZK60) alloys.     

以变性淀粉为基质涂膜保鲜液的制备与应用研究

为研究变性淀粉对于食品保鲜的应用效果和扩大其应用范围。以溶液共混法制备变性淀粉/壳聚糖涂膜液,加入纳米氧化锌和尼辛改善膜的性能,研究不同被膜对鲜切冬瓜的保鲜效果。制成不同涂膜液对鲜切冬瓜进行处理,在室温下贮存。结果表明：纳米氧化锌和尼辛的加入能明显增强涂膜液的抑菌性能;同时,变性淀粉价格较壳聚糖低,具有很广阔研究价值和应用前景。     

Enhancement of the productivity of tea (Camellia sinensis) secondary metabolites in cell suspension cultures using pathway inducers

Tea cell suspension culture is an alternative method for the synthesis of secondary metabolites. For the separation of cells, different concentrations of pectinase were used and a concentration of 0.5% was found to be the optimum concentration for the separation of cells (41.7%) in the culture medium than the other two concentrations (33.3 and 25.0%). The separated cells were cultured in liquid MS medium using different PGR combinations. The time taken for the cells to reach stationary phase, under different PGRs, ranged from 17 to 21 d. The maximum cell density was found in IAA and 2, 4-D medium at 21 d followed by 2, 4-D. Results revealed that the amount of secondary metabolites such as catechins were high with stationary phase when compared to other growth phases (lag and log phases). Different concentrations of shikimic acid (10, 20, and 30 mM) were added to the stationary phase of cell culture in the bioreactor and the secondary metabolite content was analyzed. Synthesis of polyphenols, catechins, caffeine, and other secondary components were high (33.87, 22.85, and 4.66%) with 20 mM shikimic acid treatment than the other two concentrations.     

Influence of Welding Parameters on Morphologyand Alloys' Transition of Weld Deposits

The quantity of alloys and the quality of weld layers are main factors influencing the chemical ingredient,microstructure and durability of hardfacing deposits,they also directly affect components' service life and alloys' utilization ratio.In this paper,these factors and control measures are analyzed.     

Analysis on Refining the ZLD11 Nuclear

The ZLD11 alloys containing Sr have been prepared by adding AlSr master alloy and the refinement effect of Sr on the microstructure are investigated with different contents of Sr in the finish alloys such as 0.04%,0.06%,0.08%and 0.10% Sr to change the grain size of ZLD11 alloy in mass, both microstouctve observation and gain size statistical analysis have been used to discover the proper additions of Sr. The effects of the main alloying elements on properties of ZLD11 alloy, as well as the smelting process are introduced. The results indicate that AlSr master alloy as a crystal refiner with X metal mold casting process has an effective grain refinement for ZLD11 alloy, the best refinement effect were obtained with addition of 0.08% Sr.     

猪骨蛋白酶解物对冷藏大黄鱼肌肉脂质氧化的影响

为抑制冷藏大黄鱼肌肉的脂质氧化劣变,将不同浓度(0、0.5%、1.0%和1.5%)的猪骨蛋白酶解物添加到大黄鱼肌肉中,通过观察和分析4℃冷藏条件下鱼肉感官品质及酸价、过氧化值、硫代巴比妥酸(TBA)值的变化情况,研究猪骨蛋白酶解物对冷藏大黄鱼肌肉脂质氧化的影响。结果显示,与对照组相比,添加不同浓度猪骨蛋白酶解物的各处理组鱼肉酸价、过氧化值、TBA值均显著降低(P<0.05),鱼肉感官品质显著提高(P<0.05),但不同浓度处理组之间的差异并不显著;0.5%浓度的猪骨蛋白酶解物即可有效抑制冷藏大黄鱼肌肉脂质的初级氧化产物和二级氧化产物的生成,对控制大黄鱼冷藏期间的肌肉脂质氧化具有明显效果。     

五香‘绿岭1号’薄皮核桃烘烤工艺研究

以‘绿岭1号’薄皮核桃为原料,从烘烤工艺出发,在不添加抗氧化剂的前提下,对比不同烘烤温度下薄皮核桃的干燥速率和氧化程度,优化五香薄皮核桃的烘烤条件,达到缩短烘烤时间、降低氧化程度的目的。结果表明,‘绿岭1号’薄皮核桃在60~90℃梯度升温烘烤条件下,干燥时间、氧化程度均明显低于其他烘烤方式,并且产品质量良好。因此‘绿岭1号’薄皮核桃的最佳烘烤条件是60~90℃梯度升温,其次是持续80℃烘烤。     

Review on the Research of High-strength Wrought Magnesium Alloy ZK60

ZK60 magnesium alloy is one of high-strength wrought magnesium alloys. Owing to its high strength and low density, it has nearly the highest strength to density ratio among existing materials. Because its strength approximates to high-strength aluminum alloy 7075, it has promising application future. The history of magnesium alloy ZK60 and researches on its microstructure, mechanical properties, surface treatment, and the effects of alloy elements and microelements are reviewed . Further more, the authors put forward methods to improve its microstructure and mechanical properties and prospected the development future of this alloy in the aspects of surface treatment and application.     

壳聚糖基抗菌保鲜膜制备工艺的优化

为提高壳聚糖基抗菌保鲜膜的强度,以拉伸强度为指标,考察丙三醇、聚乙烯醇、纳米TiO_2和纳他霉素添加量对壳聚糖基抗菌保鲜膜拉伸强度的影响,在此基础上利用响应面法优化其制备的工艺参数,并采用扫描电镜(SEM)观察其微观结构。结果表明,壳聚糖基抗菌保鲜膜最佳制备工艺参数为:丙三醇添加量为0.8%、聚乙烯醇添加量为0.75%、纳米TiO_2添加量为0.08%、纳他霉素添加量为0.075%。在此条件下,壳聚糖基抗菌保鲜膜性能参数为:拉伸强度为12.37 MPa,断裂伸长率为34.08%,膜厚度为0.65 mm,透湿量为563 g/(m~2·24 h),透氧系数为2.294×10~(-15)mL·m~(-2)·s~(-1)·Pa~(-1),透光率为57.4%。扫描电镜观察结果表明,壳聚糖基抗菌保鲜膜表面光滑、连续、细致,各组分具有良好的相容性。