High performance 1689-nm quantum well diode lasers

1689-nm diode lasers used in medical apparatus have been fabricated and characterized. The lasers had pnpn InP current confinement structure, and the active region consisted of 5 pairs of InGaAs quantum wells and InGaAsP barriers.     

PURE STATE APPROACH TO $C(X)×_\alpha Z_n$

ＰＵＲＥ ＳＴＡＴＥ ＡＰＰＲＯＡＣＨ ＴＯ Ｃ（ｘ）_αＺ_nＬＩＢＩＮＧＲＥＮ；ＬＩＮＱＩＮＧ（ＩｎｓｔｉｔｕｔｅｏｆＭａｔｈｅｍａｔｉｃｓ，ＡｃａｄｅｍｉａＳｉｎｉｃａ，Ｂｅｉｊｉｎｇ１０００８０，Ｃｈｉｎａ．Ｐｒｏｊｅｃｔｓｕｐｐｏｒｔｅｄｂｙｔｈ?..     

计算复特征灵敏度的代数法

对于复特征灵敏度分析问题，文中给出了一种代数法求解公式。从理论分析的角度来说，所提出的方法既适全于单频，也适合于重频。为了说明算法的数值稳定性，文中给出了严格的数学证明。     

合成金属有机(高分子)铁磁体

本文介绍了纯有机(高分子)磁体及金属有机(高分子)磁体的种类、结构和发展慨况,并概述了近年来我们所合成的常温稳定二茂铁型有机(高分子)铁磁体及其应用前景.     

高考预效度的混合估计

用传统的预测效度估计法估计高考预测效度，其估计值往往偏低。为此，本文应用回归分析中混合估计理论提出了高考预测效度的混合估计。这种估计是预测效度的无偏估计，并解决了预测效度估计值偏低的问题。     

CONVERGENCE ON RANDOMLY TRIMMED SUMS WITH A DEPENDENT SAMPLE

§１．ＩｎｔｒｏｄｕｃｔｉｏｎａｎｄＲｅｓｕｌｔｓＬｅｔ｛Ｘｎ，ｎ１｝ｂｅａｓｅｑｕｅｎｃｅｏｆｒａｎｄｏｍｖａｒｉａｂｌｅｓｗｉｔｈａｃｏｍｍｏｎｄｉｓｔｒｉｂｕｔｉｏｎｆｕｎｃｔｉｏｎＦ（ｘ）ａｎｄｌｅｔＸｎ１Ｘｎ２…Ｘｎｎｂｅｔｈｅｏｒ...     

Coboundaries of irreducible markov operators onC(K)

LetK be a compact Hausdorff space, and letT be an irreducible Markov operator onC(K). We show that ifgεC(K) satisfies sup _N ‖Σ _j ^=0N T ^j g‖<∞, then (and only then) there existsfεC(K) with (I − T)f=g. Generalizing the result to irreducible Markov operator representations of certain semi-groups, we obtain that bounded cocycles are (continuous) coboundaries. For minimal semi-group actions inC(K), no restriction on the semi-group is needed.     

金催化化学发光新体系——苯并吡喃化学发光分析法测定金矿中的痕量金

本文提出了一种测定矿样中痕量金的化学发光分析法,氯化6,7-二羟基-2,4-二甲基苯并吡喃-H_2O_2化学发光体系,方法的检出限为7ppb。工作曲线线性范围是10～1000ppbAu,测定的相对标准偏差小于7％。应用本法测定矿样中的金,结果良好。     

Sensitive monitoring of humic acid in various aquatic environments with acidic cerium chemiluminescence detection.

In this research, a simple, sensitive chemiluminescence (CL) method for the determination of humic acid (HA) in water samples was first developed based on the redox reaction between humic acid and cerium(IV) in the acidic condition. Different with the former redox CL reaction which occurred in alkaline solution, no enhancers were needed and neither precipitation nor a second contamination would occur in the present CL system. Comparing with other spectrometric methods, we find that the proposed analysis system had better applicability and accuracy. Under the optimal experiment conditions, the CL peak height was linear with the concentration of HA in the range of 0.03 to 10.0 microg mL(-1). The detection limit is 0.01 microg mL(-1) (S/N = 3), and the relative standard deviation was 2.3% for 0.5 microg mL(-1) HA solution with eleven repeated measurements. The present CL method was successfully applied to the determination of HA in tap water, spring water and river water samples with good recovery from 90.0 to 110.0%. A possible CL mechanism was proposed based on the results of UV and fluorescence spectrometry and the CL spectrum of HA. It was speculated that the semi-quinone radicals in the excited state were the emitters.     

PERMANENCE AND GLOBAL STABILITY TO A NONAUTONOMOUS NONLINEAR DISCRETE SINGLE SPECIES SYSTEM

In this paper,we study some permanence and global stability to a nonau- tonomous nonlinear discrete single species system,and obtain some sufficient condition of global stability to the system.