The Two-Point Codes with the Designed Distance on a Hermitian Curve in Even Characteristic

In Homma M and Kim SJ [2], the authors considered two-point codes on a Hermitian curve defined over fields of odd characteristic. In this paper, we study the geometry of a Hermitian curve over fields of even characteristic and classify the two-point codes whose minimum distances agree with the designed ones.     

生长曲线模型中回归系数阵的极大似然估计的精确分布

对于生长曲线模型,基于理论发展和应用效果的考虑,本文引入了Gauss型误差．在此误差下,本文研究了模型中回归系数阵的极大似然估计的精确分布,求出了此分布的密度和特征函数．     

葛仙米对丁草胺胁迫的响应

研究了丁草胺对可食用蓝藻葛仙米(Nostoc sphaeroides)生理和代谢活性的影响．用不同浓度的丁草胺处理葛仙米,结果显示低浓度(5 mg·L-1)丁草胺使其光合作用、呼吸作用和光合系统Ⅱ活性增强,高浓度丁草胺(>5 mg·L-1)限制其光合作用、呼吸作用和光合系统Ⅱ活性．同时丁草胺对葛仙米膜结构和功能具有破坏作用,随着丁草胺处理浓度增大,质膜透性不断增大,丙二醛和超氧自由基阴离子含量升高；在低浓度丁草胺处理时,类胡萝卜素含量增加,超氧化物歧化酶(SOD)活性增强,高浓度丁草胺处理时,类胡萝卜素含量降低,SOD活性下降；表明葛仙米对低浓度的丁草胺胁迫具有一定的耐受能力,但高浓度的丁草胺对其生理和代谢构成威胁；针对目前葛仙米野生生境中丁草胺的用量,建议限制丁草胺在葛仙米产地的使用,以保护日益稀缺的葛仙米资源．     

The response of microstructure to processing in a series of poly(siloxaneimide) copolymers

Poly(siloxaneimide) (PSI) segmented copolymers exhibit organized microdomains if the blocks are sufficiently incompatible. As with neat diblock and triblock copolymers, the processing route employed to prepare films of PSI materials is expected to influence the dimensions and/or morphology of the resultant microstructure. In this work, small-angle neutron scattering (SANS) is utilized to characterize the disordered microstructure found in films of a series of PSI copolymers which are subjected to solvent casting and various thermal treatments. Microstructural dimensions such as the periodicity and correlation length are deduced from the Teubner-Strey (TS) model for disordered microemulsions. The scattering intensity of each copolymer up to q = 5.0 nm^?1, where q is the scattering vector, is found to scale as q^?2.8+?0.1. Results indicate that processing the materials as cast films or as melt-pressed films allowed to cool slowly has a small, but discernible, effect on microstructural characteristics. SANS profiles of films quenched from elevated temperatures reveal a clear transition in microdomain periodicity, which correlates well with the glass transition temperature of the imide microphase in these and other materials of similar chemical structure. © 1993 John Wiley & Sons, Inc.     

利用谱线宽度测人发中的微量元素

通过实验证明了可以利用谱线宽度做永久工作曲线用于光谱定量分析。给出了用于测量人发中微量元素Ｃｕ，Ｚｎ，Ｆｅ和Ｃａ的永久工作曲线，利用这些工作曲线对实际样品进行了测定，所得结果与用ＩＣＰ－ＡＥＳ测得的结果相吻合。     

Experimental investigation on large deflection response of a frame impacted by a moving body

This paper reports on the experimental investigation of the dynamic large deflection response of a portal frame impacted at its midspan by a body moving at a certain speed. Both the deflection and velocity vs. time curves of the midspan and the dynamic history of a number of desired locations were recorded during the process of response. On the basis of the test data, the momentum and kinetic energy conversion between the frame and the moving body in the impact process are realized, and the occurrence and expansion of plastic regions are described. Investigation results show that the initial collision is approximately ideally inelastic, and that the elastic deformation plays a considerable role in the response though the input energy is much larger than the maximum elastic energy capacity of the beam member; therefore, in a general impact, the energy ratio should not be regarded as a sufficient criterion for a rigid—plastic solution. The ratios of the impulse transferred to and the energy absorbed by the frame in the initial collision to that carried by the moving body before impact is only related to the ratiobetween the equivalent mass of the frame paticipating in the initial collision and the mass of the impacting body, having nothing to do with the impacting velocity to a certain extent.     

On the reliability of unsaturated hydraulic conductivity calculated from the moisture retention curve

In comparison with direct measurements of unsaturated hydraulic conductivity, the methods of calculations from the moisture retention curve are attractive for their fast and simple use and low cost. These are the main reasons for their increasing use, mainly in spatial variability studies. On the other hand, it is known that their applicability is limited. The possibility of the use of the retention curve to indirectly determine hydraulic conductivities is analyzed as follows. The theoretical derivation of the relationK(h) – (h) is briefly discussed with regards to potential sources of inaccuracy. The sensitivity of the algorithm forK(h) calculation is studied as a response to possible inaccuracies in the retention curve determination. Conclusions about the usability of calculated hydraulic conductivities are drawn.     

甲烷分子在碱性催化剂上的吸附与酸碱活化机理

以碳酸锶为甲烷吸附活化的模型催化剂，用切换变应答、ＣＨ４（ＣＯ２）－ＴＰＤ等技术，对甲烷的吸附、碱性对催化剂性能的影响进行了研究，结果表明，甲烷在碳酸锶上的活化显示出明显的酸碱活化机理特征，瞬变应答及ＴＰＤ结果均证明，甲烷在碳酸锶表面有较强的吸附，其脱附温度约３１０℃，关联结果表明，甲烷转化率及Ｃ２烃收率与催化剂表面ＳｒＯ碱性中心浓度有非常一致的顺变关系，因此催化剂表面的酸碱中心可能是甲烷的选择活     

钢中Si、Mn的电子探针定量分析与标样

采用特制的Fe-Si、Fe-Mn合金系列标样，用电子探针测定了钢或铁基合金中低含量的Si和Mn元素、与用纯元素作标样、经ZAF修正的结果相比较，提高了分析准确度．