磷脂酰甘油与缺钙光系统Ⅱ的相互作用

对磷脂酰甘油(PG)对缺钙光系统Ⅱ(d~C~aPSⅡ)放氧活性的影响及其作用机制进行了研究。结果表明,PG除能促进PSⅡ的放氧活性以外,还对PSⅡ系统表现出新的作用,即PG可以使PSⅡ颗粒因缺钙而受抑制的放氧活性得到恢复;外加Ca^2^+可使PG表现出对d~C~aPSⅡ放氧活性的更大促进作用,且随Ca^2^+浓度的增加,促进作用也越显著。PG的作用就在于恢复蛋白的正常结构,而PG与Ca^2^+形成的配合物可以优化这种结构而使缺钙PSⅡ颗粒的放氧活性得到增强。     

离子轰击产生湍层氮化硼

用高分辨率透射电子显微镜检查了N+2离子轰击后的氮化硼样品.发现在片状六方形氮化硼sp2层的弯折区,有0.35mm晶面间距的湍层氮化硼形成.虽然其形成机制尚不清楚,但是基于束流–固体相互作用观点的讨论可能是了解湍层氮化硼结构生长过程的关键所在.     

BaTiO3晶体自抽运相位共轭特性研究

研究了多种Rh:BaTiO₃和Ce:BaTiO₃晶体样品的受激背向光折变散射自抽运相位共轭特性和响应时间特性.结果表明,入射光与晶体a面或b面法线的夹角较大时,自抽运相位共轭光有更高的反射率、更快响应时间.利用前向二波耦合特性和相向二波耦合特性对实验现象给予合理的解释.实验结果表明,多数Ce:BaTiO₃晶体比Rh:BaTiO₃晶体的共轭光反射率高. 关键词： 钛酸钡晶体 二波耦合 自抽运相位共轭 响应时间     

微波辐射下双亚苄基环己酮衍生物的合成

芳醛与环己酮在碳酸钠水溶液中,用微波辐射相转移催化法合成了α,α′-双亚苄基环己酮(3a～3j),其中3c,3i和3j为新化合物。     

流动注射-吸光光度法测定葡萄糖共存下的果糖

利用低温下葡萄糖和果糖与K3[Fe(CN)6]反应速率的明显差异,采用流动注射-吸光光度法测定了葡萄糖存在下的果糖。该法对果糖的测定范围为2．0～20mg·ml-1,当C果/C糖≥1．0时,萄萄糖无明显干扰。对蜂蜜样品进行测定并与滴定法对照,相对误差为-2．8％～2．9％。     

边值系统的能控性与能观测性问题

把抽象系统的能控性和能观测性推广到由强连续双半群描述的抽象边值系统,给出了相应的边值系统能控性的充要条件,并研究了能观测性与能控性之间的对偶关系.最后作为例子,研究了双曲系统能控性.文中所得的结果可用于讨论现代物理系统中出现一类边值系统的能控性与能观测性问题.     

Analysis of thermal conductivity in tree-like branched networks

Asymmetric tree-like branched networks are explored by geometric algorithms. Based on the network, an analysis of the thermal conductivity is presented. The relationship between effective thermal conductivity and geometric structures is obtained by using the thermal-electrical analogy technique. In all studied cases, a clear behaviour is observed, where angle (δ ,θ ) among parent branching extended lines, branches and parameter of the geometric structures have stronger effects on the effective thermal conductivity. When the angle δ is fixed, the optical diameter ratio β^* is dependent on angle θ . Moreover, γ and m are not related to β ^* . The longer the branch is, the smaller the effective thermal conductivity will be. It is also found that when the angle θ < δ / 2, the higher the iteration m is, the lower the thermal conductivity will be and it tends to zero, otherwise, it is bigger than zero. When the diameter ratio β ₁< 0.707 and angle δ is bigger, the optimal k of the perfect ratio increases with the increase of the angle δ ; when β ₁> 0.707, the optimal k decreases. In addition, the effective thermal conductivity is always less than that of single channel material. The present results also show that the effective thermal conductivity of the asymmetric tree-like branched networks does not obey Murray's law.     

Accurate and rapid error estimation on global gravitational field from current GRACE and future GRACE Follow-On missions

Firstly, the new combined error model of cumulative geoid height influenced by four error sources, including the inter-satellite range-rate of an interferometric laser (K-band) ranging system, the orbital position and velocity of a global positioning system (GPS) receiver and non-conservative force of an accelerometer, is established from the perspectives of the power spectrum principle in physics using the semi-analytical approach. Secondly, the accuracy of the global gravitational field is accurately and rapidly estimated based on the combined error model; the cumulative geoid height error is 1.985× 10^-1~m at degree 120 based on GRACE Level 1B measured observation errors of the year 2007 published by the US Jet Propulsion Laboratory (JPL), and the cumulative geoid height error is 5.825× 10^ - 2~m at degree 360 using GRACE Follow-On orbital altitude 250~km and inter-satellite range 50 km. The matching relationship of accuracy indexes from GRACE Follow-On key payloads is brought forward, and the dependability of the combined error model is validated. Finally, the feasibility of high-accuracy and high-resolution global gravitational field estimation from GRACE Follow-On is demonstrated based on different satellite orbital altitudes.     

Evolution property of soliton solutions for the Whitham－Broer－Kaup equation and variant Boussinesq equation

Using the standard Painlevé analysis approach, the (1+1)-dimensional Whitham－Broer－Kaup (WBK) and variant Boussinesq equations are solved. Some significant and exact solutions are given. We investigate the behaviour of the interactions between the multi-soliton-kink-type solution for the WBK equation and the multi-solitonic solutions and find the interactions are not elastic. The fission of solutions for the WBK equation and the fusions of those for the variant Boussinesq equation may occur after their interactions.     

对叔丁基甲苯的直接电解氧化

由对叔丁基甲苯合成对叔丁基苯甲醛,主要有化学氧化法、空气(或氧气)催化氧化法和电化学氧化法。化学氧化法通常使用二氧化锰作氧化剂,在浓硫酸中氧化合成对叔丁基苯甲醛。此法的主要缺点是产生大量的硫酸锰,需回收处理。另外,浓硫酸介质腐蚀设备且对环境有一定影响。空气催化氧化