Hilbert空间初等算子的值域闭

Ａ,Ｂ,Ｃｉ,Ｄｉ（ｉ＝１,…,ｍ）为Ｌ（Ｈ）中紧算子,初等算子（Ｘ）＝ＡＸ＋ＸＢ＋ｍｉ＝１ＣｉＸＤｉ,本文讨论值域闭的问题,得到如下结果：Ｒ（Ａ）或Ｒ（Ｂ）不闭,则Ｒ（）不闭;若Ｒ（Ａ）,Ｒ（Ｂ）,Ｒ（Ｃｉ）,Ｒ（Ｄｉ）（ｉ＝１,２,…,ｍ）均闭,则Ｒ（）闭;又令初等算子１（Ｘ）＝ＡＸ＋ＸＢ＋ＣＸＤ,Ｒ（Ｃ）与Ｒ（Ｄ）均不闭,则Ｒ（１）不闭。     

高斯序列的最大值与和的联合渐近分布

设｛Ｘｉ，ｉ≥１｝是标准高斯序列，具有ＥＸｉ＝０，ＥＸ２ｉ＝１与ｒｉｊ＝ｃｏｖ（Ｘｉ，Ｘｊ）．得到了（ｒｉｊ）满足一定的条件时最大值与和具有渐近独立性．平稳情形则作为特例被涉及．     

Levy不等式的推广

设Ｂ为一可分的赋范空间（Ｘｉ）ｉ＝１是Ｂ值独立，对称的随机元Ｓｎ＝ｘ１＋．．．Ｘｎ（ｎ〉１），若Ｑ（ｎ）是（１，２，．．．ｎ）的一些子集构成的集合并使，对Ｑ（ｎ）中任意两个元素Ｍ，Ｎ都有Ｍ∩Ｎ等于Ｍ，Ｎ或Х则我们有Ｐ（ω：ｓｕｐ‖∑Ｘｉ‖〉ｔ）≤２Ｐ（‖Ｓｎ‖〉ｔ）。     

关于外平面图的边面全染色

本文证明了：若Ｇ为简单外平面图，则（ｉ）当Δ（Ｇ）≥４时，Δ（Ｇ）≤Ｘｅ（Ｇ）≤Δ（Ｇ）＋１；（ｉｉ）当Δ（Ｇ）＝３时，４≤Ｘｅ（Ｇ）≤５，且Ｘｅ（Ｇ）＝５当且仅当Ｇ－Ｅ＇含有奇圈分支，其中Ｅ＇为Ｇ的割边集合，Δ（Ｇ）为Ｇ的点最大度，Ｘｅ（Ｇ）为Ｇ的边面全色数。     

二烷基膦酸CYANEX272萃取钴（Ⅱ）的动力学

在２９８±１Ｋ下用生长液滴法研究了（２，４，４－三甲基戊基）次膦酸（ＣＹＡＮＥＸ２７２，ＨＡ）－煤油溶液从硫酸介质中萃取Ｃｏ（Ⅱ）的动力学，提出发生在界面区的两步反应为萃取过程速率控制步骤，即：Ｃｏ２＋＋２ＨＡ（ｉ）ＣｏＡ２（ｉ）十２Ｈ＋ＣｏＡ２（ｉ）＋２Ｈ２Ａ２（ｏ）ＣｏＡ２·２ＨＡ（ｏ）＋２ＨＡ（ｉ）（ｏ）、（ｉ）分别标记有机相和界面区物种．经测定，正向反应活化能为３３．７ｋＪ·ｍｏｌ－１，萃取平衡的焓变为４２．１ｋＪ·ｍｏｌ－１     

点泛圈偶图的一个充分条件

设Ｇ是连通偶图,（Ｘ１,Ｘ２）是其顶点的二分类,｜Ｘ１｜＝｜Ｘ２｜＝ｎ,δ（Ｇ）≥ｔ≥３。证明了若任意ｕ,ｖ∈Ｘｉ蕴含｜Ｎ（ｕ）∪Ｎ（ｖ）｜≥ｎ－（ｔ－２）,ｉ＝１,２,则当ｔ＝７时Ｇ是点泛圈偶图。     

The Ordered Fragments in Nucleotide Sequence and Molecula rEvolution

定义了核苷酸序列的有序片段（Ｘ１Ｘ２…Ｘｋ）ｎ，Ｘｉ表示碱基的嘌呤嘧啶分类或强弱键分类，ｎ为重复次数．通过统计分析６．８Ｍｂｐ资料找出全部ｋ＝２，３的有序片段，发现若干有序片段的含量具有较好的进化相关性．     

领域并与点泛圈偶图

设Ｇ是连通偶图，（Ｘ１，Ｘ２）是其顶点的二分类，│Ｘ１│＝│Ｘ２│＝ｎ，δ（Ｇ）≥ｔ≥３。证明了若任意ｕ，ｖ∈Ｘｉ→│Ｎ（ｕ）∪Ｎ（ｖ）│≥ｎ－〔ｔ－１／２〕，ｉ＝１，２，则Ｇ是点泛圈图。     

非定常线性系统的稳定性与不稳定性

本文讨论非定常线性系统的稳定性和不稳定性．我们推广了文［２］的结果，证明了对Ｘ’＝Ａ（ｔ）ｘ，当Ａ（ｔ）的特征根λｉ（ｔ）有Ｒｅλ（ｔ）≤－ａ＜ｏ，ｉ＝１，…，ｋ，Ｒｅλｉ（ｔ）≥ａ ＞ｏ，ｉ＝ｋ＋１，…，ｎ，且Ａ（ｔ）的变化率很小时，Ｘ’＝Ａ（ｔ）ｘ有ｋ维解空间其解指数型收敛，ｎ－ｋ维解空间其解指数型发散．我们还用出了Ａ（ｔ）的变化率界的估计，并将此结果应用于大系统的稳定性分解．     

关于最小可行图的一个结果

给出了关于（Ｘ１，Ｘ２，Ｘ３，Ｘ４）的可行图Ｇ＝ＵＧｉ是最小可行图的充分必要条件：Ｇ是连通单圈图；或Ｊ∈（１，２，３，４），当∩Ｘｉ≠时，∩Ｇｉ是树，对任意整数ｎ给出了关于（Ｘ１，Ｘ２，…Ｘｎ）的最小可行图的若干性质，推广了已有的结果。     

一般灰色趋势关联系统及其分析方法研究

结合灰色趋势关联度，利用数学一般系统理论，提出了一般灰色趋势关联系统模型，作为该模型的应用，对灰色趋势关联分类、灰色趋势关联聚类、灰色趋势关联预测等三种应用方法进行了研究．     

Influence of chemical liquids on the fatigue crack growth of the AZ31 magnesium alloy

The fatigue crack growth behavior of an AZ31 magnesium alloy was investigated by comparing the effect of zirconate and phosphate chemical liquids. The morphology, components, and phase compositions of the chemical depositions at the fatigue crack tip were analyzed by employing scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and X-ray diffraction (XRD), respectively. For samples with and without the chemical liquids, their stress-intensity factor values at the fatigue crack tip were compared by using a stress-strain gauge. The results demonstrated that a zirconate film (Zr_xO_y·Zn_xO_y) and a phosphate film (Zn₃(PO₄)₂·4H₂O and MgZnP₂O₇) could be formed on the fatigue crack-surface at the fatigue crack tip. The stress distribution was changed because of the chemical depositions and the causticity of the chemical liquids. This could decrease the stress-intensity factor value and thus effectively cause fatigue crack closure, which reduces the fatigue crack growth rate. Moreover, it was found that the fatigue crack closure effect of zirconates was more positive than that of phosphates.     

渐近拟非扩展型映象不动点的迭代逼近

 去掉了已有文献中的条件:"对任意子列{x_ni} {x_n},当‖Tⁿix_ni-x_ni‖^→0时就有‖Tx_ni-x_ni‖^→0"后,研究了Banach空间中渐近拟非扩展型映象不动点的迭代逼近问题;所得结果推广和发展了已有文献中的成果.     

Studies on reduced extent method for inhibited thermokinetics of enzyme-catalyzed reaction

The thermokinetic reduced extent equations of reversible inhibitions for Michaiels-Menten enzymatic reaction were deduced, and then the criteria for distinguishing inhibition type was given and the methods for calculating kinetic parameters,K _M,K _i andv _m were suggested. This theory was applied to inverstigate the inhibited thermokinetics of laccase-catalyzed oxidation ofo-dihydroxybenzene bym-dihydroxybenzene. The experimental results show the inhibition belongs to reversible competitive type,K _M=6.224×10⁻³ mol·L⁻¹,K _i=2.363×10⁻² mol·L⁻¹. Xiong Ya: born Sep. 1961, Ph. D. graduate student. Curent research interest is in biothermochemistry research Supported by the National Natural Science Foundation of China     

Smog chamber studies of ozone formation potentials for isopentane

The incremental reactivity and ozone formation potential of isopentane have been studied with chamber experiments and computer simulations. The chemical mechanism used in the computer simulations is an isopentane sub-mechanism from the Master Chemical Mechanism （MCM）. The results from the chamber experiments suggest that the MCM can well simulate i-C5H12-NOx chamber experiments. The heterogeneous reaction of NO2 and water is an important source for OH radicals in the chamber experiments. The photolysis of HONO is responsible for the initiation of isopentane in photochemical reactions. The reaction rate constant for NO2 → HONO was determined to be 3.9×10-4―5.9×10-3 min-1 by conducting 3 sets of CO-NOx-air irradiations. 5 sets of isopentane-NOx irradiations under different conditions were performed in our chamber. Compared with the experiment with a low relative humidity （RH）, an increase in RH can increase the reaction rate of NO2 with H2O, so that the peak ozone occurs earlier. When isopentane is predominant over NOx, the peak ozone concentration is largely dependent on NOx concentrations.     

200 MW四角切圆锅炉燃烧器浓淡比对NOx排放影响的数值研究

以某热电厂200MW四角切圆浓淡煤粉燃烧锅炉为对象,通过数值模拟获得了该炉最大连续出力工况(BMCR)下炉膛内的流场、温度场及炉膛出口的NO_x浓度,并进一步通过数值模拟探讨了改变水平浓淡煤粉燃烧器浓淡比时对炉内燃烧及NO_x生成情况的影响.数值结果表明:在BMCR工况下,计算值与实际运行的在线仪表的记录值基本一致;当浓淡比增大时,NO_x生成量并不是单调的,而是先降低后升高;其中最佳浓淡比为5∶1,且在此基础上采用"缩腰型"配风有助于进一步降低NO_x生成量.其计算结果可供同类锅炉实际运行时参考.     

线性交换子的加权估计

 多线性交换子T_b(f)(x)=∫_Rⁿ∏_i=1^m(b_i(x)-b_i(y))k(x,y)f(y)dy在L^p(Rⁿ)(1K是一个标准的Calderón-Zygmund核.主要研究交换子Mf(x)=sup_x∈Q∫_Q|f(y)|dy,其中f∈L_loc(Rⁿ),x∈Rⁿ,Q是任何包含x的方体,并用Sharp极大估计得到了该多线性交换子在Herz空间的一个加权有界性.     

Infield superconducting properties of nano-sized Ag added Cu_(0.5)Tl_(0.5)Ba_2Ca_2Cu_3O_(10-δ)

Infield superconducting properties of {(Ag)_x/CUTl-1223};(x = 0, 0.5,1.0.2.0 and 4.0 wt %) nanoparticlessuperconductor composites were investigated under different applied magnetic field up to H = 8 T. The increase in critical temperature {T_c(0)} and decrease in normal state resistivity(p_o) were observed with increasing contents of Ag nanoparticles in CuTl-1223 superconducting matrix. The value of T_c~(onset)(K) remained almost unaffected by applying external magnetic field, but a decreasing trend in T_c(0) was observed by increasing the value of external applied magnetic field. The transition region below T_c~(onset)(K) showed Arrhenius behavior due to thermally activated flow of magnetic vortices. Enhancement in flux flow activation energy(U_o) and suppression in transition width(ΔT) of CuTl-1223 phase with addition of Ag nanoparticles showed the improvement in flux pinning strength of superconductor.     

我国黄海浒苔绿潮暴发海域环境因子季节性变化及年际变化分析

【目的】掌握环境因子与浒苔绿潮之间的相互影响关系,为绿潮形成机制研究和半岛绿潮灾害防治提供科学资料。【方法】通过整理收集浒苔绿潮暴发重点海域的历史数据和现场调查数据,系统分析浒苔绿潮暴发期间以及浒苔绿潮暴发前后关键环境因子(温度、盐度、pH值、溶解氧DO、无机氮、磷酸盐和叶绿素a)的季节性变化、年际变化。【结果】南黄海海域表层海水温度2—8月份呈上升趋势,年际变化不大;盐度季节性和年际变化幅度不大;pH值2—8月份呈现先下降后升高再下降的趋势,历年来2月份呈上升趋势,8月份呈下降趋势;DO浓度2—8月份呈现先下降后升高再下降的趋势,年际变化很小;无机氮浓度2—8月份呈现先上升后下降的趋势,历年来2月份比较稳定,8月份呈下降趋势;磷酸盐季节性变化无规律,年际变化不大;浒苔绿潮暴发期间底层海水叶绿素a浓度高于表、中层。【结论】表层海水温度、盐度和无机氮都适宜于浒苔的生长,这是导致浒苔发生发展,乃至导致绿潮发生的区域环境因素;浒苔绿潮与DO、磷酸盐关系不明显;浒苔暴发导致浮游植物的生长受到极大限制。     

柴油机SCR尿素喷射方式研究

鉴于柴油机选择性催化还原系统尿素喷射特性与氮氧（NO_x）转化效率密切相关,本文搭建SCR系统小样试验台,NO和NH₃作为主要试验用气,研究了不同氨氮比和不同温度条件下V₂O₅-WO₃/TiO₂催化剂的氨存储、氨泄漏以及NO_x转化效率的影响.结果表明:氨氮比越大,氨存储量的建立时间越短,NO_x转化效率的提升就越快;氨氮比为0.22时,15 s内NO_x转化效率从0增大到4.3%;当氨氮比为0.30时,15 s内NO_x转化效率从0增大到8.7%;随着氨氮比的增大氨泄漏会提前出现;氨氮比先大后小的喷射方法有利于改善NO_x转化效率.采用氨氮比先大后小的喷射方法,进行ETC标准循环测试,NO_x比排放从8.26 g/（kW·h）减少到1.91 g/（kW·h）,NH₃泄漏均值为5×10-6,峰值为18×10-6,满足国V排放法规要求.