激光陀螺磁灵敏度特性研究

分析、计算了激光陀螺的磁灵敏度特性,并进行了磁灵敏度试验.试验结果及分析表明：在腔体加工准确度不变的情况下,采用合理的设计可以大大降低激光陀螺在某些方向上的磁灵敏度,同时磁试验结果对于设计激光陀螺的磁屏蔽结构具有一定的实用价值.     

化学位移估算研究ATP构象随溶液pH值的变化

利用Johnson和Bovey的理论和方法计算了不同扭曲角χ(O4′－C1′－N9－C4)的ATP(5′-三磷酸腺苷)分子中糖环质子H1′和H2′由于环流效应引起的化学位移.H1′的化学位移与扭曲角χ有较强的依赖关系,反映了ATP在溶液中细微的构象变化.将计算结果与实验结果比较,证明在本文讨论的pH值范围(1～10)内,Mg2＋加入后,ATP的扭曲角χ在230～360°范围内变化.随溶液的pH值减小,ATP分子的构象由trans 构象通过-gauche构象转变为cis构象. 从而证明在酸性条件下, ATP倾向于以cis构象存在,而在碱性条件下trans构象更为稳定,从另一方面支持了在酸性条件下N1参与配位而在碱性条件下N7参与配位的结论.在讨论中也考虑了由pH变化所引起的环流强度的变化.     

Topologically Irreducible Representations and Radicals in Banach Algebras

It is shown that the topologically irreducible representationsof a normed algebra define a certain topological radical inthe same way that the strictly irreducible representations definethe Jacobson radical and that this radical can be strictly smallerthan the Jacobson radical. An abstract theory of ‘topologicalradicals’ in topological algebras is developed and usedto relate this radical to the Baer radical (prime radical).The relations with topologically transitive representationsand standard representations in the sense of Meyer are alsoexplored. 1991 Mathematics Subject Classification: 46H15, 46H25,16Nxx.     

All-optical frequency multiplication/recovery based on a semiconductor optical amplifier ring cavity

A novel scheme for all-optical frequency multiplication/recovery based on a semiconductor optical amplifier ring cavity is proposed and investigated numerically. The results show, for a 2.5 GHz driving pulse train, it can be generated 5-25 GHz repetition rate pulse trains with low clock amplitude jitter, polarization independence and high peak power. Furthermore, the extraction of the clock signal from a pseudorandom bit sequence signal can be realized based on the proposed scheme.     

Performance of ring oscillators composed of gate-all-around FETs with varying numbers of nanowire channels using TCAD simulation

In this paper, we investigate the performance of ring oscillators composed of gate-all-around (GAA) silicon nanowire (NW) field-effect transistors (FETs) with four different numbers of NW channels, for sub-10-nm logic applications. Our simulations reveal that ring oscillators with double, triple, and quadruple NW channels exhibit improvements of up to 50%, 85%, and 97%, respectively, in the oscillation frequencies (f_osc), compared to a ring oscillator with a single NW channel, due to the large drive current, in spite of the increased intrinsic capacitance of a given device. Moreover, our work shows that the f_osc improvement ratio of the ring oscillators becomes saturated with triple NW channels with additional load capacitances of 0.1 fF and 0.01 fF, which are similar to, or less than the intrinsic device capacitance (∼0.1 fF). Thus, our study provides an insight for determining the capacitive load and optimal number of NW channels, for device development and circuit design of GAA NW FETs.     

Na/THF- Mediated cleavage of organic disulfides/diselenides. An efficient and one-pot regioselective method to the synthesis of β-hydroxy sulfides/selenides

A new, facile, and efficient methodology for synthesizing β-hydroxy sulfides/selenides has been reported. In this study, 1,2-epoxide ring opening was used as the synthetic protocol, and this reaction was examined using metallic sodium with no additional catalyst. This lead to the synthesis of the desired ring-opened products. Relatively short reaction times, mild reaction conditions, a simple work-up, moderate to good yields of products, and remarkable regioselectivity of the nucleophilic attack were other important features of this study.     

INJECTIVE PRECOVERS AND MODULES OF GENERALIZED INVERSE POLYNOMIALS

Let (S,≤) be an ordered set. Recall that (S,≤) is artinian if every strictly decreasingsequence of elements of S is ?nite, and that (S,≤) is narrow if every subset of pairwiseorder-incomparable elements of S is ?nite. Let S be a commutative monoid. Unl…     

On Skew Triangular Matrix Rings

For a ring R, endomorphism α of R and positive integer n we define a skew triangular matrix ring T _n (R, α). By using an ideal theory of a skew triangular matrix ring T _n (R, α) we can determine prime, primitive, maximal ideals and radicals of the ring R[x; α]/ ? x ⁿ  ?, for each positive integer n, where R[x; α] is the skew polynomial ring, and ? x ⁿ  ? is the ideal generated by x ⁿ .