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71.
谭连生 《数学物理学报(B辑英文版)》1995,(3)
THEDISTURBANCELOCALIZATIONPROBLEMFORSINGULARSYSTEMSTanLiansheng(WuhanInst.ofMath.Sci.,Chin.Acad.ofSci.,Wuhan430071,China.)Abs... 相似文献
72.
本文给出了一类线性约束下不可微量优化问题的可行下降方法,这类问题的目标函数是凸函数和可微函数的合成函数,算法通过解系列二次规划寻找可行下降方向,新的迭代点由不精确线搜索产生,在较弱的条件下,我们证明了算法的全局收敛性 相似文献
73.
以有机硅CH_3Si(OC_2H_5)_3和NH_2(CH_2)_3Si(OC_2H_5)_3为交联剂,对层状化合物α-Zr(HPO_4)_2·H_2O进行交联,经灼烧分别得到2种不同层间距的层柱型分子筛SiO_2-Zr(HPO_4)_2。用XRD、GC、NMR等方法对交联反应过程进行了研究,结果表明,交联剂在反应过程中发生水解、缩聚。某种聚合态硅选择性地嵌入α-Zr(HPO_4)_2·H_2O层间。 相似文献
74.
The rupture force to separate the third strand and the duplex within a triplex DNA was measured by means of atomic force spectroscopy. The tip and the sample surfaces were functionalized by oligodeoxyribonucleotides 5'-TTCTTCTTTCTTTTCCTTTTCTTTCTTCTTACTTCTCTCTCTC TCTCTCT-SH-3'. The sample surface was hybridized with 5'-AAGAAGAAAGAAAAGGAAAAGAAAGAAGAA-3' to form a double strand DNA on the surface prior to the force measurements. These sequences form triple helices with 30 base pairs under a pH of 5.8 and in the presence of 2.0 mM spermine. Signals of rupture of single and multiple triplex DNA were observed in the force distance curves. Rupture force histograms revealed a force of 42.6 +/- 1.9 pN from 24 independent measurements at a tip velocity of 400 nm/s to separate the third strand from duplex DNA. The velocity dependence of the rupture force quantum indicates a thermal dissociation process similar to that of rupturing a ds-DNA. The number of rupture events was controlled by adding oligonucleotides 5'-AAGAAGAAAGAAAAGGAAAAGAAAGAAGAA-3' either to reduce or to initiate triplex formation. 相似文献
75.
Discovery of nitric oxide in marine ecological system and the chemical characteristics of nitric oxide 总被引:1,自引:0,他引:1
ZHANG Zhengbin XING Lei WU Zhenzhen LIU Chunying LIN Cai & LIU Liansheng Institute of Marine Chemistry Ocean University of China Qingdao China 《中国科学B辑(英文版)》2006,49(5):475-480
Nitric oxide was discovered in both the lab and the alga culture pond of Daya Bay (1―300 m3) before the growth of alga reached the maximum. The results included: (1) NO was detected before the growth of alga reached the maximum in the case of red tide alga and food alga, and the concentration of NO decreased rapidly after the growth maximum; (2) the curve between NO con-centration and time indicated that the concentration of NO in the daytime was more than that at night, and the maximal concentration of NO appeared in the midday (1―3 pm); (3) the growth of alga reached the maximum in the alga culture pond of Daya Bay in about 8―10 d, and NO was discovered in 5―7 d; (4) the measured NO concentration was 10-9 mol/L, 10-9―10-8 mol/L, and 10-8 mol/L for Haeterosigma akashiwo, mixed alga in Daya Bay and Chaetoceros Curvisetus individually; (5) the relation of illumination with NO production was discussed. 相似文献
76.
Seawater samples of the sea surface microlayer were obtained from the ocean, coastal waters, and laboratory imitation experiments adopting glass plate, rotating drum, screen, and funnel samplers. The result was that surface microlayer samples of thickness 50 microm could be taken, not by the popular screen and funnel techniques, but by glass plate or rotating drum techniques. The layer of sudden change of physical and chemical properties in the surface microlayer was found at 50 microm below the sea-air interface. These physical and chemical properties included tens of physical and chemical parameters, such as concentrations of organic matter, nutrients, and dissolved trace metals, biochemical oxygen demand, chemical oxygen demand chlorophyll-a, surface tensions, and pH. Therefore, it was suggested that the layer of sudden change of physical and chemical properties in surface seawater should serve as a basis for defining the sea surface microlayer should, and be regarded as the practical operational thickness of the sea surface microlayer. The apparent sampling thickness of the sea surface microlayer from surface seawater should be 50+/-10 microm. 相似文献
77.
In this paper, we discuss the following inequality constrained optimization problem (P) minf(x) subject tog(x)0,g(x)=(g
1(x), ...,g
r
(x))
, wheref(x),g
j
(x)(j=1, ...,r) are locally Lipschitz functions. TheL
1 exact penalty function of the problem (P) is (PC) minf(x)+cp(x) subject tox R
n
, wherep(x)=max {0,g
1(x), ...,g
r
(x)},c>0. We will discuss the relationships between (P) and (PC). In particular, we will prove that under some (mild) conditions a local minimum of (PC) is also a local minimum of (P). 相似文献
78.
79.
The syntheses of both 5-amino-6-nitro-1,10-phenanthroline and 5,6-diamino-1,10-phenanthroline (starting from 5-nitro-1,10-phenanthroline) are described in detail. 相似文献
80.