丙三醇溶液声致发光中的黑体辐射谱

利用U型管圆锥泡声致发光装置,测量到了丙三醇溶液中圆锥泡声致发光的光谱和光脉冲。结果表明,测量得到的发光光谱为光滑的连续谱,且与理论模拟得到的黑体辐射谱相吻合,拟合温度分布于2 600～3 500 K范围内。文章从空间和时间两方面分析了圆锥泡空化发光中存在黑体辐射的原因：较大的气泡体积(气泡塌缩半径为1.4 cm)与较长的发光时间(几十微秒)。另外,实验研究表明随着发光波长的增长,光脉冲宽度变宽,从而进一步证明了圆锥泡声致发光中的黑体辐射机制。最后,利用测量得到的发光光谱和脉冲计算得到了发光光强为0.18 J,远远高于其他方式得到的声致发光光强。     

溶液样品温度对ICP光源发射强度的影响

通过光电检测法研究了溶液样品温度在20,40和60 ℃条件下,对电感耦合等离子体(ICP)光源发射强度的影响。实验结果表明,随着溶液温度的提高,元素钡、铜和锌的谱线强度有明显的增强。观察了在不同溶液温度下,谱线强度随光源观察高度和载气压力的变化规律, 发现温度的提高使最佳观测高度位置降低,而最佳载气压力升高。     

乙醇—丙烯酸体系中乙醇的γ辐解研究

研究了乙醇-丙烯酸体系在低剂量下的γ辐解产物H_2、2,3-丁二醇及乙醛的生成.结果表明,乙醛不是在α-羟乙基自由基的歧化反应中生成的,而是来源于刺迹中的快反应;在该体系中丙烯酸(未与溶剂化电子反应)可清除H原子,其反应速率常数k_4=7.5×10~(9)mol~(-1)s~(-1);2,3-丁二醇由α-羟乙基自由基的再结合反应生成,动力学方程可表示为:G=G_0—[k_(11)/2(k_10)~(1/2)](G/K'D)~(1/2)[AAH].     

Optimal Two-Dimensional Compressed Matching

Recent proliferation of digitized data and the unprecedented growth in the volume of stored and transmitted data motivated the definition of the compressed matching paradigm. This is the problem of efficiently finding a patternPin a compressed textTwithout the need to decompress. We present the firstoptimaltwo-dimensional compressed matching algorithm. The compression under consideration is the two dimensional run-length compression, used by FAX transmission. We achieve optimal time by proving new properties of two-dimensional periodicity. This enables performing duels in which no witness is required. At the heart of the dueling idea lies the concept that two overlapping occurrences of a pattern in a text can use the content of apredetermined text positionorwitnessin the overlap to eliminate one of them. Finding witnesses is a costly operation in a compressed text, thus the importance of witness-free dueling.     

液晶环氧树脂复合材料的研究进展

综述了液晶环氧树脂复合材料的国内外研究进展，介绍了液晶环氧树脂复合材料的种类和各种液晶环氧树脂复合材料的性能，并简述了液晶环氧树脂复合材料研究发展方向。     

A review of spin Hamiltonian forms for various point-group site symmetries

A review has been made of the spin Hamiltonian forms for all the 32 point groups, including linear magnetic field-dependent terms in spin operators $\hat O_1^m $ , $\hat O_3^m $ , $\hat O_5^m $ , $\hat O_1^m $ , $\hat O_3^m $ , and $\hat O_5^m $ . All spin operators, as well as their matrix elements, to be used in constructing spin Hamiltonian matrices, have been listed. The various point group aggregates for distinct spin-Hamiltonian forms have been classified. In addition, descent of symmetry point groups, useful for studying structural phase transitions, have been indicated.     

THE EFFECT OF POLAR ADDITIVES ON THE γ RADIATION INDUCED POLYMERIZATION OF STYRENE*

The γ induced polymerization of styrene in the presence of polar additives such as tributylphosphate, triethyl amine and ethanol was studied at dose rate of 5.0×10~(17) eV/ml. min. The re-sult shows that radiation induced polymerization of styrene was sensitized by the three kinds ofadditives at the approximate same rate and the experimental results were in agreement with thetheoretical calculation of WAS equation. The cause of sensitization is due to the proton transfer.     

Pauli-Dirac matrix generators of Clifford Algebras

This article presents a Pauli-Dirac matrix approach to Clifford Algebras. It is shown that the algebra C₂ is generated by two Pauli matrices i₂ and i₃; C₃ is generated by the three Pauli matrices ₁, ₂, ₃; C₄ is generated by four Dirac matrices ₀, ₁, ₂, ₃ and C₅ is generated by five Dirac matrices i₀, i₁, i₂, i₃, i₅. The higher dimensional anticommuting matrices which generate arbitrarily high order Clifford algebras are given in closed form. The results obtained with this Clifford algebra approach are compared with the vector product method which was described in a recent article [Found. Phys. 10, 531–553 (1980) by Poole, Farach and Aharonov] and with the Dirac, Rashevskii and Ramakrishnan methods of matrix generation.Supported by the National Science Foundation under Grant ISP-80-11451.