用I(I+1)展开式分析超形变带

用Bohr－MottelsonI（＋1）展开四参数转动谱公式系统分析了A～190、150区的超形变转动带．结果表明：四参数ABCD公式能够相当好地描述上述两个区的超形变带,若干核第二类转动惯量J(2)的理论计算值与实验提取值符合较好;A～190区超形变带的四参数数值关系并不支持Harris公式及ab公式的理论预期值,但相对而言,ab公式的理论预期值与实验提取值更为接近．     

用I(I+1)展开式分析超形变带

用Bohr–MottelsonI(+1)展开四参数转动谱公式系统分析了A～190、150区的超形变转动带.结果表明:四参数ABCD公式能够相当好地描述上述两个区的超形变带,若干核第二类转动惯量J⁽²⁾的理论计算值与实验提取值符合较好;A～190区超形变带的四参数数值关系并不支持Harris公式及ab公式的理论预期值,但相对而言,ab公式的理论预期值与实验提取值更为接近.     

超形变带自旋的比较指定

首次用Bohr-Mottelson公式和Harris公式同时指定A≈190区超形变带的带首自旋值.对大多数超形变带,用以上两种方法指定的自旋是一致的,而对部分超形变带则不一致.不能一致地指定自旋的和自旋指定不符合带首转动惯量系统学的超形变带,用带首转动惯量系统学或两类转动惯量系统学的方法重新指定其自旋.利用指定的自旋,拟合Bohr-Mottelson转动谱公式,研究了参数之间的关系,结果表明从Harris三参数公式导出的关系式更符合实验值.     

Bohr—Mottelson公式对超形变带的比较研究：？…

用Ｂｏｈｒ－Ｍｏｔｔｅｌｓｏｎ的两参数、三参数和四参数公式对Ａ～１９０区６１条超形变带进行了系统分析。结果显示：３个公式都能较好地拟合１９０区超形变带的Ｅ２跃迁谱,而且带自旋的确定基本一致。大部分带Ｂｏｈｒ－Ｍｏｔｔｅｌｓｏｎ的三参数数值关系符合ａｂ公式的理论预期值,小部分带的三参数值关系符合Ｈａｒｒｉｓ公式的理论预期值,一半以上带的四参数数值关系与ａｂ公式的预期值接近,而与Ｈａｒｒｉｓ公式的预期     

Bohr-Mottelson转动谱公式参数之间的新关系式

在利用Harris两参数公式研究Bohr-Mottelson转动谱公式参数之间的关系的基础上,改用Harris三参数公式,并由此提出了Bohr-Mottelson转动谱公式参数之间的新关系式,进而用I(I+1)四参数展开式计算了A～60,80,130,140,150,190区超形变偶偶核的基带和锕系和稀土区正常形变核基带,讨论了参数之间的关系,发现新关系式与实验较好地符合.     

A～190区超形变带自旋指定的再讨论(Ⅰ)偶偶核

在γ跃迁能量中扣除了ΔI=4分岔的影响后,根据ab公式,系统讨论了A～190区偶偶核超形变带,给出了绝大多数超形变带的自旋值. 部分超形变带的自旋指定值,不同于其它方法得到的结果.     

Harris公式和ab公式对超形变核转动带的适用性的比较

对A≈190区超变形转动带分别用Harris二参数公式和ab公式进行了系统分析.分析结果表明,与正常变形核动带的情况相似,Harris公式与实验有明显的系统偏离,而ab公式则与实验很接近,可以相当精确和方便地描述超变形转动带.     

190区超形变带自旋指定的再讨论

利用两类转动惯量随转动频率的变化及其相互关系,对190区Bohr-Mottelson的两参数、三参数和四参数I(I+1)展开公式指定自旋不一致的27条超形变带进行分析,发现其中18条超形变带,它们的带首自旋I₀能够从两类转动惯量随转动频率的变化及其相互关系中可靠地定出.¹⁹²Hg(2)等发生带交叉的超形变带,它们的带首自旋也可通过分析带交叉以前、两类转动惯量随转动频率的变化及其相互关系定出.     

A≈190区超形变带自旋指定的再讨论(Ⅱ)奇A核

改进了从γ跃迁能量中扣除振荡起伏部分的方法.在此基础上,采用ab公式或改进的ab公式,系统地讨论了A≈190区奇A核中的超形变带,给出了绝大多数超形变带的自旋值.部分超形变带的自旋指定值不同于其它方法得到的结果.     

190区超形变核态转动惯量的奇偶差分析

用Bohr-Mottelson的I(I+1)展开三参数公式拟合能谱所定出的展开系数,计算190区超形变带的带首转动惯量.计算结果显示:奇A核的带首转动惯量系统大于相邻偶偶核的带首转动惯量,奇奇核的带首转动惯量系统大于相邻奇A核的带首转动惯量,超形变核态带首转动惯量展现出明显的奇偶差现象.     

Nonlinear dynamics in the CO-oxidation on Pt single crystal surfaces

The types of dynamical behaviour that can be found in nonlinear systems far from equilibrium are briefly described. Then experimental manifestations of these phenomena in the CO oxidation on Pt are presented which include bistability, oscillations and chaos as well as propagating and stationary spatial patterns. It is demonstrated how a simple model can be refined to account for the observed complex behaviour.     

Liouville Type Dilatonic Potential in Locally Rotationally Symmetric Bianchi I Model

Exact solutions are obtained for a special case of locally rotationally symmetric Bianchi I models consisting of a dilaton scalar field and a Liouville type dilatonic potential interacting with an electromagnetic field coupled with gravity, and the corresponding properties of the space-time are discussed.     

“强光一号”等离子体断路开关及负载的数值计算

 等离子体断路开关（POS）是“强光一号”加速器产生短脉冲γ射线的关键器件之一。应用POS融蚀模型分析了“强光一号”加速器POS与二极管系统的基本工作过程，通过该模型计算获得了POS与二极管系统的总电流以及电子束电流，计算结果与实验结果吻合较好。计算结果表明，“强光一号”POS在工作时并未达到完全磁绝缘状态，其阻抗最终为21.5 Ω，约有60％总电流在二极管负载导通时流过POS，且融蚀模型对POS阻抗增长预测偏高，但由于电流变化较大，二极管负载电压仍能达到4.5 MV左右。     

NCl(a1Δ)/I（2P3/2）传能体系的实验研究

 利用微波放电Cl₂/He等离子体作为Cl源，对反应NCl(a¹Δ) + I(²P_3/2)→NCl(X³Σ) + I(²P_1/2)进行了实验研究，得到了较大的I(²P_1/2)自发辐射荧光信号，检测到NCl(a¹Δ，b¹Σ)自发辐射荧光光谱在存在少量I(²P_1/2)下发生的显著变化，其中NCl(a¹Δ)自发辐射荧光信号降低，同时由于I(²P_1/2)的作用，NCl(b¹Σ)自发辐射荧光信号大幅度增加。在考察各反应气体流量对I(²P_1/2)自发辐射荧光信号的影响时发现，在本次实验条件下，各种气体的最佳流量：He为1～4mmol/s, I₂为0.01～0.03mmol/s, Cl₂为1.0mmol/s左右,而HN₃流量略大于Cl₂流量时信号升高幅度开始变缓，约为Cl₂流量的两倍时信号不再有显著的变化。     

I/Q方法用于高频信号鉴相

在加速器高频相位控制环路中, 相位检测是影响控制精度的关键环节. 讨论了两种将I/Q技术用于高频信号鉴相的方法. 具体内容包括数学算法的研究和硬件系统的搭建. 两种方法分别是: 1) 利用I/Q解调模块、AD采集卡和数字处理技术进行鉴相; 2) 直接数字I/Q方法. 在第一种方法中, 提出了一种可行的、针对I/Q模块固有误差的修正算法. 第二种方法, 通过对参考相位进行(2π/N)步进调制, 获得I, Q分量. 两种鉴相方法都达到了误差<0.5°.     

Raman comparison of skin dermis of different ages: focus on spectral markers of collagen hydration

Skin aging is the most visible sign of aging of the body. This complex process involves molecular and structural alterations of the main skin constituents. The major cutaneous constituent is type I collagen that gives strength and resilience to the skin. This macromolecule possesses a particular triple helix structure and is arranged in the form of a fibrous network. Water plays a crucial role for maintaining this molecular assembly which is altered during intrinsic chronological aging. To investigate some of these structural alterations, Raman microspectroscopy was employed since this biophotonic approach permits to probe the biomolecular composition of the skin in a non‐destructive manner. In addition, type I collagen gives specific Raman vibrations; some of which being sensitive to the molecule conformation and to the water environment. In this purpose, Raman spectra of four skin samples of different ages (two samples of 40 year old and two samples of 70 year old) were collected by varying the relative environmental humidity. Our experiments highlighted spectral differences between the four samples. The analysis of the Raman data permitted to suggest a model for the interactions between collagen and water molecules and a decrease in collagen fibers compactness with chronological aging. Our study demonstrates that Raman spectroscopy can be a useful tool to investigate skin aging, with innovative applications in dermatology as well as in cosmetics. Copyright © 2013 John Wiley & Sons, Ltd.     

Characteristics of dithering cycles during the L–I–H transition on Experimental Advanced Superconducting Tokamak (EAST)

An intermediate phase (labeled I phase) with dithering cycles between the L-mode and H-mode has been observed and experimentally characterized on Experimental Advanced Superconducting Tokamak (EAST). A typical characteristics of the I phase is that the $D_{\alpha }$ signal, edge density fluctuation level and edge radiation show several kHz periodical oscillation. The analysis shows that the dithering event is at least 2 cm inside the separatrix and extends into the scrape-off layer (SOL) region. It is found that this dithering occurs in plasma with double null (DN) or upper single null (USN) configuration and cannot be observed in plasma with lower single null (LSN) configuration where the ion $B\times \mathrm{?}B$ drift direction is ‘unfavorable’, i.e. away from the X-point, in this device. The dithering cycle length ($\mathrm{\Delta }{t}_{\text{<mi mathvariant="italic" is="true">dither</mi>}}$) has no clear dependence on the heating power. Both stored energy and density increase during the dithering phase and the increasing rates decrease with $\mathrm{\Delta }{t}_{\text{<mi mathvariant="italic" is="true">dither</mi>}}$. The evolution of density profiles during the L–I–H transition is analyzed and presented.     

Electron absorption spectra of univalent copper-, silver-, and gold-thiourea complexes in aqueous solutions

Using data on the stability of complex forms, electron absorption spectra of copper (I)-, silver (I)-, and gold (I)—thiourea complexes in an aqueous solution M_itu_j (Ag: i=1, 2, j=1–3; Cu: j=1, 2; Au: j=2) are calculated from the spectra of solutions of a known analytical composition. Parameters of particular bands of the absorption spectra of these complexes are given. It is found that the integral intensity of the spectra of the solutions is proportional to the concentration of thiourea in the solution with high accuracy. The same is also valid for the spectra in solutions that contain mercury (II) and thiourea. The total intensity of longwave bands in the spectra of the complexes is proportional to the number of ligands in a molecule of the complex. Institute of Ionorganic Chemistry, Siberian Branch of the Russian Academy of Sciences, 3, Lavrent’ev Ave., 630090, Novosibirsk-90, Russia, Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 64, No. 4, pp. 458–462, July–August, 1997.     

Increase in Tc and spin glass transition in La0.9Ca0.1Mn1−yCryO3 (y=0, 0.1 and 0.2)

We report on the structural, frequency dependent ac susceptibility, dc magnetization and magnetoresistance (MR) measurements on polycrystalline samples of La_0.9Ca_0.1Mn_1−yCr_yO₃ (y=0, 0.1 and 0.2) prepared by sol-gel technique. For y=0, a paramagnetic to ferromagnetic transition is observed at T_c=136 K. Both for y=0.1 and 0.2, T_c increases from 136 to 180 K. For y=0, the imaginary part of the ac susceptibility shows a broad transition at T_f<T_c which does not depend very much on the frequency. However, for y=0.1 and 0.2, the frequency dependence resembles that of a spin glass. Though all the three samples show a semi-conducting behavior between 300 and 5 K, a negative MR is observed corresponding to T_c and T_f. The value of MR decreases for the Cr substituted samples.