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     

PbS纳米微粒对溴化银微晶乳剂的化学增感作用

发现了PbS纳米微粒对溴化银乳剂的化学增感作用,对PbS和Na₂S₂O₃对卤化银乳剂的增感作用进行了比较,研究了增感剂用量、增感温度和pAg值、溴化银的晶型等因素的影响,以及PbS纳米微粒与HAuCl₄的协同增感效应.     

以pH敏感相分离高分子为载体的酶联荧光免疫分析法测定人IgG

p H敏感高分子因其独特的 p H敏感性质而在药物的控制释放 [1,2 ] 、分子分离 [3 ] 以及生物传感器 [4 ]等方面得到应用 .应用于免疫分析时 ,要求 p H敏感高分子在溶液 p H 7.4左右波动时做出响应 ,过多偏离生理 p H会对免疫反应生成的抗原 -抗体复合物造成不同程度的破坏 .目前 ,p H敏感高分子并未在免疫分析中广泛应用 ,这主要是由于高分子的相转变 p H大多在 4或 1 0左右[5,6] .我们 [7] 曾合成了3 7℃下相转变 p H在 5 .6左右的 p H敏感高分子 ,并将其作为免疫反应载体 ,建立了乙肝表面抗原的分析系统 ,虽然其相转变 p H比以往的高…     

TS—1的丙烯环氧化性能研究

采用连续淤浆反应器,在40℃,0.4MPa和0.6MPa下,考察了粉状TS－1催化剂在丙烯与过氧化氢环氧化反应中的反应性能,表明TS－1催化剂的单程寿命不低于80h,通过对TS－1催化剂的IR及XRD的表征及比表面分析,发现其骨架结构和骨架钛未发生变化,催化剂部分失活是由于非骨架活性钛的流失及催化剂孔道的堵塞造成的,并可以用甲醇洗脱再生。