与积分有关的一类函数极限的再探讨

用马克劳林公式探讨带有定积分的函数极限     

荧光光度法测定环境水样中镁的含量——基于与邻菲啰啉生成络合物而产生的荧光增敏作用

在pH 10.0的缓冲介质中,以235 nm和360 nm为发射波长测定时,邻菲啰啉试剂的荧光因与镁(Ⅱ)反应生成了络合物而得到增敏,其增敏的程度(△F)与镁(Ⅱ)的质量浓度之间在0.1～2.0 mg·L-1范围内呈线性关系.此反应的检出限(3s/b)为0.038 mg·L-1.应用此方法测定了3种不同来源的水样中镁的含量,测定值的相对标准偏差(n=6)在1.3%～1.6%之间.在此样品的基础上用标准加入法做回收试验,测得回收率在98%～103%之间.     

属性层次模型AHM在质量评估中的应用

一种新的无结构决策方法—属性层次模型AHM.与Saaty提出的层次分析法AHP是不同的.AHM既不需要计算特征向量,也不需要进行一致性检验,运算量小,科学性强.通过对一个质量评估问题的分析,说明属性层次模型AHM是简便易行、行之有效的决策方法.     

Synthesis, Crystal Structure and Inhibition of N-2-Thiophenesulfonyl-α-L-phenylalanine Ethyl Ester on K562 Cell Proliferation

The title compound N-2-thiophenesulfonyl-α-L-phenylalanine ethyl ester has been synthesized. Complete assignments were achieved by IR, MS, 1H NMR and single-crystal X-ray diffraction analyses. Using MTT assay, the inhibitory rate of the title compound on K562 cells (chronic myeloid 1eukemic cells) was measured and the result of preliminary bioassay showed that the title compound possesses antiproliferation effects on K562 cells. In order to investigate the relationship between structure and activity of the target compound, we report its crystal structure and biological behavior in the present paper. Crystallographic data: C15H17NO4S2, Mr = 339.42, monoclinic, space group P21, flack = –0.15(12), a = 5.7916(10), b = 11.5078(19), c = 12.924(2) , β = 97.781(3)o, Z = 2, V = 853.4(2) 3, Dc = 1.321 g/cm3, F(000) = 356, –7≤h≤7, –10≤k≤14, –15≤l≤15, R = 0.0628, wR = 0.1540 and μ(MoKα) = 0.327 mm-1. The molecule comprises a benzene and a thiofuran rings, and the intramolecular N(1)–H(1A)…O(1) makes a five-membered ring of O(1)–C(6)–C(5)–N(1)–H(1A).     

一个被席夫碱配体支撑的一维梯形水簇Bpcmda·4H_2O的合成和表征

合成了化合物Bpcmda·4H2O ,利用IR、元素分析、1H NMR和单晶X-射线衍射进行了表征.详细的结构分析表明Bpcmda·4H2O中的溶剂水分子以O-H...O氢键的相互作用形成了一个沿着b轴伸展的独一无二的梯形水簇.     

用定义证明极限时不等式放大的原则和实例

介绍用定义证明极限时不等式放大的原则     

无穷限反常积分收敛时被积函数的极限状态

根据无穷限反常积分∫a^＋∞f（x）dx收敛的柯西准则和定积分的性质,讨论被积函数f（x）当x→∞时。的极限状态,并得出当无穷限反常积分∫a^＋∞f（x）dx收敛且f（x）在[a,＋∞）上连续,或者无穷限反常积分∫a^＋∞f（x）dx绝对收敛时,存在数列{xn}∩[a,＋∞]且xn→＋∞（n→∞）,使limn→∞xnf（xn）=0.     

N′叔丁氨基羰基-N-(5-取代苯基-2-呋喃甲酰基)硫脲的合成及对白血病K562细胞增殖的影响

合成;N′-叔丁氨基羰基-N-（取代苯基呋喃甲酰基）硫脲;MTT法;白血病K562细胞     

Effect of STI-induced mechanical stress on leakage current in deep submicron CMOS devices

The shallow trench isolation (STI) induced mechanical stress significantly affects the CMOS device off-state leakage behaviour. In this paper, we designed two types of devices to investigate this effect, and all leakage components, including sub-threshold leakage ($I_{\rm sub})$, gate-induced-drain-leakage ($I_{\rm GIDL})$, gate edge-direct-tunnelling leakage ($I_{\rm EDT})$ and band-to-band-tunnelling leakage ($I_{\rm BTBT})$ were analysed. For NMOS, $I_{\rm sub}$ can be reduced due to the mechanical stress induced higher boron concentration in well region. However, the GIDL component increases simultaneously as a result of the high well concentration induced drain-to-well depletion layer narrowing as well as the shrinkage of the energy gap. For PMOS, the only mechanical stress effect on leakage current is the energy gap narrowing induced GIDL increase.     

关于单调函数的单侧极限的Heine定理

Heine定理的基本形式、函数极限定义及确界原理,文中讨论了单调函数的单侧极限存在的充要条件,通过证明可见,相应的结果可表示为更强的形式.