反光板(合作目标)反射率测量仪

本文介绍了反光板（合作目标）反射率测量仪的研制。仪器采用对称双光路比较测量法，给定两束相等光通量的光束，分别作为参考光束和测试光束，并用分束器实现原光路取样，从而解决了合作目标反光板入射光线与反射光线重合不能用常规测试方法来检测的难题。由于采用对称双光路的方法，入射光通量是相对恒定的，不受外界因素影响，从而使反射率测量仪达到精度高、重复性好和环境要求低的设计要求。     

配合物1,3-二甲基-2-二茂铁基甲基苯并咪唑的量子化学DFT研究

苯并咪唑及其衍生物具有良好的生物活性和荧光性质[1,2],在DNA拓扑酶抑制剂、HIV逆转录酶的抑制剂、分子探针等领域已有广泛应用,一直以来都是广大学者研究的热点[3]。苯并咪唑类化合物是一类活性很强的内吸型杀菌剂,它的主要作用方式是植物病原的R-微管蛋白结合,破坏R-微管蛋白的功能,抑制真菌的有丝分裂和形态建构。然而,随着使用时间的增加,病菌的抗生越来越强,导致在部分地区失效,给农业生产带来巨大损失。所以迫切需要寻找高效、新型的杀菌剂。近些年来,二茂铁衍生物因其广泛的生物活性,如抗癌、杀菌、杀虫、抗炎及调节植物生长等…     

SYNTHESIS OF SOME SULFUR-CONTAINING SPIROINDOLE DERIVATIVES

Abstract

The synthesis of some new sulfur-containing spiroindole derivatives is reported. Fluorinated 3′-aryl-2′-phenylimino-spiro[3H-indole-3,6′[4,5′-pyrazolin][4,3-d]thiazolo]2(1H)-ones were prepared by the reaction of 5-(2-oxo-3-indolinylidene)-3-aryl-2-phenylimino-4-thiazolidinones with hydrazine hydrate. The compounds have been characterized on the basis of elemental and spectral studies.     

Beatings in the Spin Echo Signal in Media Having a Doublet Structure of the Spectrum

We have obtained an analytical expression for the twopulse echo signal arising in nonresonant excitation of a condensed medium with a nonuniformly broadened spectrum of doublet structure by two pulses of an electromagnetic field of different durations and of the same amplitude. It is shown that in the case where the differences between the carrying frequency of exciting pulses and the central frequencies of the spectral lines differ considerably, beatings are formed in the signal of the twopulse echo. The rate of decay of the amplitude of these beatings is found to depend only on the time of reversible and irreversible relaxation, and their circular frequency is determined by the shift of the spectral lines relative to each other. A technique for separate determination of the inhomogeneous width of the lines and time of the irreversible transverse relaxation is suggested which is based on the analysis of the twopulse echo signal beatings.     

Multipole effects in non-Kramers doublet system PrMg3

We performed ultrasonic measurements on a single crystal of PrMg₃. The characteristic Curie-type softening was observed in temperature dependence of transverse mode (C₁₁-C₁₂)/2 below 8 K down to 0.8 K. This softening in PrMg₃ is caused by a non-Kramers Γ₃ doublet ground state having electric quadrupoles O_u and O_v and magnetic octupole T_xyz. The elastic constant (C₁₁-C₁₂)/2 shows a minimum at 25 K, which cannot be explained by the quadrupole susceptibility based on the crystal electric field (CEF) levels. However, considering higher order (l=4) multipole, namely electric hexadecapole, the minimum around 25 K was well reproduced. At lower temperatures, a shoulder anomaly in elastic constant being deviated from the Curie-type softening was observed around 100-800 mK in (C₁₁-C₁₂)/2. This anomaly is unaffected by magnetic fields up to 14 T.     

相干驱动场的线宽对电磁感应透明的影响

考虑相干驱动场的线宽，探讨了其对双激发态原子三能级系统中的电磁感应透明现象的影响，得到结论：相干驱动场的线宽抑制了介质对弱探测光的透明。     

A Mössbauer study of octahedral site symmetries in systems Co x Mn3−x−y Fe y O4 and Ni x Mn3−x−y Fe y O4

A Mössbauer study of cation distribution in systems Co _x Mn_3?x?y Fe _y O₄ and Ni _x Mn_3?x?y Fe _y O₄ has been made. It has been found that in both systems all specimens withy<0.6 value exhibit quadrupole doublets corresponding to site symmetries Fe³⁺(I) and Fe³⁺(II) of octahedral site. As more and more cobalt or nickel is introduced into the matrix the intensity of the inner quadrupole doublet increases while on introducing iron that of the outer quadrupole doublet increases. After a certain concentration of iron the inner doublet starts becoming more intense. It is suggested that this arises possibly from the substitution of cations in the second co-ordination sphere of Fe³⁺(I) and Fe³⁺(II) sites. Fory>0.6 the Mössbauer spectra show relaxation effects.     

Autler-Townes doublet in the absorption spectra for the transition between excited states of cold cesium atoms

Autler-Townes splitting in absorption spectra of the excited states 6 2 P 3/2-8 2 S 1/2 of cold cesium atoms confined in a magneto-optical trap has been observed.Experimental data of the Autler-Townes splitting fit well to the dressed-atom theory,by which the fact of the cold atoms dressed by cooling/trapping laser beams is revealed.The results of the theoretical fitting with experiment not only told us the effective Rabi frequency cold atoms experienced,but also could be used for measuring the probability amplitudes of the dressed states.     

Doublet bands at borders of A ≈ 130 island of chiral candidates: Case study of ~(120)I

Positive-parity doublet bands were reported in ~(120)I. Based on these, we discuss the corresponding experimental characteristics, including rotational alignment, and re-examine the corresponding configuration assignment.The self-consistent tilted axis cranking relativistic mean-field calculations indicate that the doublet bands are built on the configuration πh_(11/2)■νh_(11/2)~(-1). By adopting the two quasiparticles coupled with a triaxial rotor model, the excitation energies, energy staggering parameter S(I), B(M1)/B(E2), effective angles, and K plots are discussed and compared with available data. The obtained results support the interpretation of chiral doublet bands for the positive-parity doublet bands in ~(120)I, and hence identify this nucleus as the border of the A ≈ 130 island of chiral candidates.     

πg9/2(⊕)vh11/2 doublet bands in A～100 mass region

Using the model with one particle and one hole coupled with a triaxial rotor, the πg(-1)(9/2)(⊕)vh11/2 doublet bands in the A ～ 100 mass region are studied, and compared with the πh11/2(⊕)vh(-1)(11/2) doublet bands.It is found that the calculated results for the configuration of πg(-1)(9/2)(⊕)vh11/2 are very similar the results for a pure h11/2 proton particle and a neutron quasiparticle with λn =ε5. After including the pair correlation, the model describes the candidate chiral doublet bands in 106Rh successfully, which supports the interpretation of chirality geometry.