不同南瓜品种对嫁接黄瓜幼苗生长及抗寒性的影响

本试验对黑籽南瓜、中国圆、长媳、灯笼、香炉、大白、西葫芦(早青一代)、割瓜、中国长等9 个南瓜品种与津杂2 号黄瓜的嫁接亲合性、嫁接苗生长势及抗寒性进行了初步研究。结果表明,供试南瓜品种与黄瓜嫁接亲合性均较好;砧木对嫁接苗生长势有一定影响,嫁接苗粗壮,生长速度快;对嫁接苗抗寒性有显著影响。长媳南瓜品种综合性状优于黑籽南瓜,香炉南瓜和大白南瓜的综合性状接近黑籽南瓜。     

末次冰期以来东海内陆架沉积反映的海平面变化

对东海内陆架泥质沉积区MD06-3042孔(27°05.4′N,121°24.1′E,水深62m,岩芯长34.1m)样品进行了高分辨率的粒度分析和14C年代测试,重建了末次冰期以来东海内陆架区的海平面及沉积环境的变化.14.0ka左右,海平面已经到达现今海平面下62m等深线的位置,大量沉积物在此沉积.13.0~4.2ka之间,受海流等多种因素影响,少量沉积物在此沉积.4.2~3.2ka之间,现代东海内陆架的泥质沉积主体在该岩芯附近快速堆积.东海内陆架的泥质沉积体由北向南,由内向外逐渐形成,具有阶段性.     

高浓度氯化钙水热环境下氢氧化镁颗粒生长行为研究

以石灰乳-卤水法制备的氢氧化镁为原料,对不同水热环境下高浓度氯化钙对氢氧化镁颗粒形貌的影响进行了研究。通过扫描电镜(SEM)、X射线衍射仪和氮气吸附比表面积分析仪(BET)对产物的比表面积和形貌进行表征。结果表明,较高的温度和高浓度氯化钙的存在有利于晶体的发育生长,其产物的分散性较好,粒径均匀并呈六方片状晶体,比表面积由22.17 m2/g变为14.84 m2/g。对水热条件下氯化钙对晶体生长的作用进行了机理分析,CaCl2的存在使得氢氧化镁基元在晶体表面横向叠加,促进了六方片状氢氧化镁颗粒的生成,并提出氢氧化镁颗粒的最稳定晶型为六方片状。     

可再分散性乳胶粉性能影响因素探讨

采用单因素实验方法,研究了喷雾干燥时喷雾液的粘度、进料量、雾化轮转速、干燥器进出口温度等因素对可再分散性乳胶粉性能指标的影响。结果表明:喷雾液的粘度为0.30~0.15Pa.s,进料泵频率27~30 Hz,雾化轮转速(2~3)×104r/min,干燥塔进风温度150~200℃,出口温度90~100℃时,所得可再分散性乳胶粉外观均匀、固含量高、堆积密度大、平均粒径小、无结块现象,性能指标达到工业生产使用要求。该研究为可再分散性乳胶粉的生产及在建筑砂浆中的应用,提供了可靠的参考依据。     

Single grain Rb-Sr dating of euhedral and cataclastic pyrite from the Qiyugou gold deposit in western Henan, central China

The Rb-Sr isotopic dating of pyrite mineral from ore deposits can directly provide mineralization age. However, many geological factors may affect the Rb-Sr isotopic system,which baffles application of this method. Employing ultra-low procedural blank Rb-Sr method,we have dated pyrites separated from the No. 4 breccia pipe of the Qiyugou gold deposit,western Henan Province. Single grains of euhedral pyrite crystal with few microcracks yield an isochron age of 126 ± 11 Ma, which represents time of the main mineralization stage of the deposit. Pyrite grains of cataclastic type show nevertheless scattered Rb-Sr isotopic composition and no reasonable isochron can be defined. Crystal morphology and mineral inclusion studies reveal that Rb and Sr of pyrite mineral probably are preserved mainly in biotite, K-feldspar, and sericite mineral inclusions. The dating results likely suggest that cataclastic pyrite is not suitable for the Rb-Sr dating due to modification of the Rb-Sr isotopic system by later hydrothermal activity of fluid.     

湖北省平原湖区粮食安全研究

从粮食生产的条件和现状、粮食生产存在的问题3个方面分别对湖北省平原湖区的粮食安全状况进行了分析;从粮食生产任务,粮食生产能力的建设以及合理调整农业结构3个方面提出了提高平原湖区粮食生产能力的对策.     

Dependence of mechanical behavior on grain size of metastable Ti–Nb–O titanium alloy

Cold-rolled metastable β-type Ti–38Nb-0.2O alloy was subjected to annealing treatment to obtain different precipitates and grain sizes. The influence of annealing on microstructure and mechanical properties was investigated. The alloy annealed at 673 ?K or 773 ?K exhibited a single-stage yielding with high strength and low uniform elongation, due to the residual work hardening and the precipitation of ω or α phases. The alloy annealed at above 873 ?K exhibited an obvious double yielding behavior resulting from the stress-induced martensitic transformation. The grain growth kinetics of single β phase alloy is sensitive to temperature, and it is suggested that the existence of oxygen decreases the grain growth exponent and increases the required activation energy for grain growth. The critical stress for slip decreased monotonously with the increase of grain size, following the classic Hall-Petch relationship. However, the critical stress for martensitic transformation decreased to a minimum and then increased again, as the grain size increased. The results are worth for design of the heat-treatment parameters of the Ti–38Nb-0.2O alloy for engineering applications.     

带非线性边界条件的一类离散梁方程正解的存在性

用Krasnoselskii不动点定理给出带非线性边界条件的一类离散梁方程正解的存在性结果, 其中: λ>0为参数; h: ［2,T］_Z→［0,∞)为函数; f: (0,∞)→R连续且在u=0处允许有奇性, 在u=∞处超线性增长.     

坛紫菜新品系WO144-3的主要经济性状分析

］对杂交选育的坛紫菜新品系(WO144-3)的生长性状、耐高温性能、叶绿素含量、藻胆蛋白含量等指标进行了测定,并与一个野生型品系(WT)进行了对比分析。结果表明:1)经过20 d培养,WO144-3品系叶状体长度从4 cm增加到138 cm,平均日增长率为17.59%,是WT品系的1.92倍;叶状体厚度为(17.41±0.33)μm,约为WT品系的70%。培养开始时,WO144-3品系长宽比约为WT品系的2倍,20 d后增加到5倍。但WO144-3品系的平均日增重率与WT品系没有显著差异。2)在30 ℃高水温培养10 d后,WO144-3品系叶状体的长度是WT品系的1.70倍;此外,高温处理对WO144-3品系的Fv/Fm没有显著影响,而WT品系的显著降低了59%。3)WO144-3品系的藻胆蛋白、藻红蛋白和藻蓝蛋白的含量分别为WT品系的2.05、2.74和1.42倍,但在叶绿素a和别藻蓝蛋白的含量上两品系没有显著差异。由此可得出:WO144-3是一个窄/薄叶品系,具有生长速度快、耐受高温胁迫、藻胆蛋白含量高等优点,具备应用于生产的潜力。     

Si纳米线的制备方法与器件应用

以气-液-固(VLS)、气-固-固(VSS)、固-液-固(SLS)和氧化物辅助生长(OAG)机制为主线,着重介绍与评论了几种主要的Si纳米线的制备方法,如激光烧蚀沉积(LAD)、化学气相沉积(CVD)、热蒸发和金属(Au,Fe,Ni和Al)催化生长等.简要介绍了Si纳米线及其阵列在场效应晶体管、场发射器件、太阳电池、传感器以及集成电子器件等方面的应用.最后,讨论了各种制备方法的优势与不足,指出了该研究领域今后的发展方向.