基于快速傅里叶变换和汉克耳变换的逆阿贝尔变换

激光等离子体实验中的轴对称的Ｘ光的体发射强度及光学全息干涉的测量,需要采用逆阿贝尔（Ａｂｅｌ）变换。用快速傅里叶变换（ＦＦＴ）和汉克耳（Ｈａｎｋｅｌ）变换的算法数值求解逆阿贝尔变换,具有精度高、可在频域内滤波的特点。     

RP-HPLC测定罗勒中石吊兰素的含量

建立反相-高效液相色谱法(RP-HPLC)测定罗勒(Ocimum basilicumL.)中石吊兰素的含量。用Microsorb-M V 100-5C18(4.6mm×250mm,5μm)色谱柱,甲醇:1%醋酸=86:14(V/V)为流动相,流速为0.5mL/min,检测波长为335nm。石吊兰素浓度在0.27—32.4μg/mL范围内与峰面积线性关系良好(r=0.9999),方法平均回收率大于99%(n=9)。方法简单、可靠,可应用于罗勒植物中石吊兰素的含量测定。     

Scaling Behavior between Heat Capacity and Thermal Expansion in Solids

We experimentally analyze the heat capacity and thermal expansion of reference solids in a wide temperature range from several Kelvin to melting temperature,and establish a universal double-linear relation between the experimental heat capacity C_p and thermal expansion β,which is different from the previous models.The universal behavior between heat capacity and thermal expansion is important to predict the thermodynamic parameters at constant pressure,and is helpful for understanding the nature of thermal properties in solids.     

Preparation of CdO nanoparticles by mechanochemical reaction

CdO nanoparticles of 43 nm in crystal size were successfully synthesized by the mechanochemical reaction (CdCl₂ + Na₂CO₃) with NaCl as a diluent and subsequent thermal treatment at 700°C for 2 h. The samples were characterized by differential thermal analysis (DTA), thermogravimetric analysis (TGA), X-ray diffraction (XRD) and transmission electron microscopy (TEM). Effect of calcination temperature on the crystal size of CdO nanoparticles was primarily investigated. The apparent activation energy of CdO nanoparticle formation during thermal treatment was calculated to be 12.2 kJ/mol.     

物理实验管理系统的构建与实现

介绍了通过运用网络平台构建物理实验中心的管理系统,以实现学生选课、成绩管理、教学信息管理和发布、教学资料的上网及仪器管理等一系列的功能,使物理实验中心的各项工作有序而高效.     

Spectrum analysis of all parameter noises in repetition-rate laser pulse train

The theoretical investigation of all parameter noises in repetition-rate laser pulse train was presented. The expression of power spectrum of laser pulse trains with all parameter noises was derived, and the power spectra of pulse trains with different noise parameters were numerically simulated. By comparing the power spectra with and without pulse-width jitter, we noted that pulse-width jitter could not be neglected compared with amplitude noise and timing jitter and contributed a great amount of noise into the power spectrum under the condition that the product of pulse width and angular frequency was larger than 1.     

Security analysis of a spatiotemporal-chaos-based cryptosystem

An S-box modified one-way coupled map lattice is applied as a chaotic cryptograph. The security of the system is evaluated from various attacks currently used, including those based on error function analysis, statistical property analysis, and known-plaintext and chosen-ciphertext analytical computations. It is found that none of the above attacks can be better than the brute force attack of which the cost is exhaustively quantitated by the key number in the key space. Also, the system has fairly fast encryption (decryption) speed, and has extremely long period for finite-precision computer realization of chaos. It is thus argued that this chaotic cryptosystem can be a hopeful candidate for realistic service of secure communications.     

Responses of Issatchenkia terricola WJL-G4 upon Citric Acid Stress

This study aimed to elucidate the responses of a novel characterized Issatchenkia terricola WJL-G4 against citric acid stress by performing physiological analysis, morphology observation, and structural and membrane fatty acid composition analysis. The results showed that under citric acid stress, the cell vitality of I. terricola WJL-G4 was reduced. The cell morphology changed with the unclear, uncompleted and thinner cell wall, and degraded the cell structure. When the citric acid concentration was 20 g/L, I. terricola WJL-G4 could tolerate citric acid and maintain the cell structure by increasing the intracellular pH, superoxide dismutase activity, and contents of unsaturated fatty acids. As the citric acid concentration was ≥80 g/L, the stress has exceeded the cellular anti-stress ability, causing substantial cell damage. The cell membrane permeability, the content of membrane lipids, malondialdehyde and superoxide anion increased, but the intracellular pH and superoxide dismutase activities decreased, accompanying the increase of citric acid concentrations. The findings of this work provided a theoretical basis for the responsive mechanism of I. terricola WJL-G4 under high concentrations of citric acid, and can serve as a reference for biological acid reduction in fruit processing.     

OX2(X=F，Cl，Br，I，At)中的离域π63键

本文在理论层面上研究了OX₂(X=F,Cl,Br,I,At)分子的电子结构,结果表明其中存在离域π⁶₃键,氧原子采取sp²杂化方式,与价层电子对互斥理论预测的结果不符. 提出了离域稳定化能衡量形成离域π⁶₃键对能量降低的贡献,证实离域π⁶₃键对分子结构起到了额外的稳定作用. 这些现象可以总结为一种配位效应.     

彩色负片印片颗粒指数的准确测定

分析了彩色负片印片颗粒指数σper实际测试中不同性能负片的测试特点和影响因素。印片颗粒指数的测试点应根据彩色负片的感光特性确定,为正常扩印时对应正片0．74中灰密度的负片密度点。影响印片颗粒指数值的两个主要因素是彩色相纸的反差修正系数α和彩色负片的覆盖力系数ECP;建立了α和ECP的实验求取方法,并通过对几种负片参量的实际测定,分析和说明了参量变化对印片颗粒指数数值的影响程度和应进行的修正。