线宽测量在光电光谱分析中的应用

本文介绍了利用谱线宽进行光电光谱分析的方法，实验结果表明：在０．０１ｍｇ．ｍｌ＾－１到４ｍｇ．ｍｌ＾－１的浓度范围内，谱线宽度与浓度成很好的线性关系。     

Evaluating departures from fair representation

Computer–intensive estimates are introduced to evaluate departures from proportionality between the numbers of electors in a partition of a voting population and the numbers of representatives in the corresponding partition of the elected representation. At the first stage a pair of indices is proposed, one to evaluate the total strength of the departures and the other to indicate to what extent they are due to over–representation increasing (or decreasing) with the number of electors in a group. The properties of the indices are examined in suitably defined stochastic models which describe this type of over–representation. Since the values of the indices are strongly influenced by the distribution of electors in the given partition, a second stage of estimation is performed in order to get some [partition–free] information on the existence of a monotone size representation, and, if it exists, on its strength. The relevant transformation is based on intensive computer simulation in the introduced models. The methods proposed are applied to the results of the 1991 election of the Polish Scientific Research Council, which distributes funds among universities, scientific institutions and individual groups of researchers.     

LIMIT CYCLES AND BIFURCATION CURVES FOR THE QUADRATIC DIFFERENTIAL SYSTEM （III）m=0 HAVING THREE ANTI-SADDLES （I）

For the quadratic system: x=-y δx lx2 ny2, y=x(1 ax-y) under conditions -10 the author draws in the (a, ()) parameter plane the global bifurcationdiagram of trajectories around O(0,0). Notice that when na2 l < 0 the system has one saddleN(0,1/n) and three anti-saddles.     

关于A.Menezes和S.Vanstone一文的注记

1987年,R.Schoof对于有限域Fq上的椭圆曲线的同构类数目得出了一个公式.1990年,A.M enezes和S.V anstone对此当q为偶数时给出了一个初等证明.本文利用Burnside引理对q为偶数时给出一个更简单的证明.     

A connectionist model of the organizational learning curve

Organizational learning can be understood as a spontaneous development of routines. Mathematically, this process can be described as a search for better paths on a graph whose nodes are humans and machines. Since the rules for connecting nodes depend on their ability to process goods, the slope of the learning curve may be connected to physical and psychological properties. Two suggestive examples are discussed. Guido Fioretti, born 1964, graduated in Electronic Engineering and obtained a PhD in Economics from the University of Rome “La Sapienza”. He is currently an assistant professor at the University of Bologna, Italy.His research interests span from decision theory to economics and organization science. In particular, he is interested in linking structural development to cognitive processes. The present article has been conceived as a theoretical underpinning of agent-based simulations of organizations. In particular, future applications of the Java Enterprise Simulator () may test the usefulness of the results derived herein.     

I-V curve oscillation observed by atomic force microscopy

Oscillation on the current-voltage curve measured by atomic force microscopy is observed when the distance between the tip and sample is large enough and beyond a critical value. The appearance of the oscillation is attributed to the excitation of electron standing waves between the tip and sample. From the first peak position and the voltage difference between the first two peaks on the current-voltage curve, the value of the work function at the detected point on silver film surface and the distance between the tip and the detected point can be calculated.     

Potential decay behavior of iron in dilute nitric acid

Potential-time decay curves were used to investigate the passivation of iron in dilute nitric acid solutions of different concentrations. The effect of sulfate ions on the decay curves was also examined. It was observed that the decay curves formed an almost flat potential segment ending after reaching the Flade potential (the potential at the end of the plateau). The duration of the plateau was a function of both the initial holding potential and the acid concentration. The addition of sulfate ions affected the decay duration without interfering with the Flade potential. This is worth noting in view of the well-known dependence of the open-circuit potential decay on both pH and on the constituents of the solution. Received: 26 February 1997 / Accepted: 14 May 1997     

Phase separation behavior of aqueous solutions of a thermoresponsive polymer

Cloud‐point and binodal curves of the LCST type were obtained for aqueous solutions of a thermoresponsive polymer, poly [2‐(2‐ethoxy)ethoxyethyl vinyl ether], poly(EOEOVE). The cloud‐point curve obtained was very flat except in a dilute region, that is the cloud‐point temperature was insensitive to the polymer concentration, resembling the cloud‐point curve for aqueous solutions of poly(N‐isopropylacrylamide). On the other hand, the binodal curve obtained was parabolic, and located within the two‐phase region of the cloud‐point curve. Accompanied with the phase separation, a sharp endothermic peak was observed in a region including the cloud‐point and binodal temperatures. The reciprocal of the osmotic compressibility ?Π/?c obtained by sedimentation equilibrium indicated that water changes from a good to poor solvent for poly(EOEOVE) with increasing temperature. Analyzing the ?Π/?c data by a thermodynamic perturbation theory, we determined the interchain interaction parameters, the hard‐core diameter d and the depth ε of the square‐well potential. Theoretical binodal and endothermic curves calculated by the perturbation theory using the estimated interaction parameters reproduced experimental ones semiquantitatively, but the theoretical binodal disagreed with the experimental flat cloud‐point curve. The disagreement at high concentrations was in the opposite direction to that expected from the sample polydispersity in the molecular weight. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 2937–2949, 2005     

Dynamical Order in Systems of Coupled Noisy Oscillators

We investigate a dynamical order induced by coupling and/or noise in systems of coupled oscillators. The dynamical order is referred to a one-dimensional topological structure of the global attractor of the system in the context of random skew-product flows. We show that if the coupling is sufficiently strong, then the system exhibits one dimensional dynamics regardless of the strength of noise. If the coupling is weak, then it is shown numerically that the system also exhibits one dimensional dynamics provided the noise is sufficiently strong. We also show that for any coupling and any noise, the system has a unique rotation number and hence all the oscillators tend to oscillate with the same frequency eventually (frequency locking). Dedicated to Professor Pavol Brunovsky on the occasion of his 70th birthday.