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141.
Thesolubilityofcompressedgasesinliquidscanbeveryhigh,whichresultsintheexpansionoftheliquids.Thes0lubilitiesofsolutesinliquidscanbereducedconsiderablybydissolutionofthegases'i.e.,thegasesactasantisolvents.Recently,somecompressedgaseshavebeenusedinmanygasantisolventpr0cesses.Understandingofthepropertiesofthecompressedgas-liquidmixtUresisofgreatimportancetoboththeoreticalstUdyandindustrialprocesses.ThetautomerismofspiropyransandtheirderivativeshasbeenstUdiedbydifferentauthors"',whichindicatedth… 相似文献
142.
在求解大规模数据的优化问题时,由于数据规模和维数较大,传统的算法效率较低.本文通过采用非精确梯度和非精确Hessian矩阵来降低计算成本,提出了非精确信赖域算法和非精确自适应三次正则化算法.在一定条件下,证明了算法有限步停止,并估计了算法迭代的复杂度.特别地,我们分析了采用随机抽样时算法在给定概率下的复杂度.最后,通过二分类问题的数值求解,比较了本文提出的随机信赖域算法,随机自适应三次正则化算法和已有算法收敛效率.数值结果表明在相同精度下,本文提出的算法效率更高,并且随机自适应三次正则化算法的效率优于随机信赖域算法. 相似文献
143.
Nan Han Rongzheng Ren Minjian Ma Chunming Xu Jinshuo Qiao Wang Sun Kening Sun Zhenhua Wang 《中国化学快报》2022,33(5):2658-2662
Applying mixed oxygen ionic and electronic conducting(MIEC) oxides as the cathode offers a promising solution to enhance the performance of solid oxide fuel cells(SOFCs). However, the phase instability in CO2-containing air and sluggish oxygen reduction activity of MIEC cathodes remain a long-term challenge for optimizing the electrochemical performance of SOFCs. Herein, a heterovalent co-doping strategy is proposed to enhance the oxygen reduction activity and CO2 tolerance... 相似文献
144.
The temperature monitoring of treated cancer cells is critical in photothermal therapy. Current methods of detecting intracellular temperatures have low accuracy and poor spatial resolution, which limits their application to photothermal therapy. Herein, a strategy for targeted recognition and selective capture of MCF-7 breast cancer cells based on fluorescent polymer poly(N-isopropylacrylamide-benzoxadiazole-2-vinyl-4,4-dimethyl azlactone, PNMV) and modified gold nanobipyramids(Au NBPs-PNMV) wa... 相似文献
145.
Exact surface energy and elementary excitations of the XXX spin-1/2 chain with arbitrary non-diagonal boundary fields 下载免费PDF全文
Jia-Sheng Dong 《中国物理 B》2023,32(1):17501-017501
We study the physical properties of the XXX spin-1/2 chain with arbitrary non-diagonal boundary fields. By using a combination of numerical analysis and analytical method, we obtain the surface energy and elementary excitations of the model. It shows that the contributions of the two boundary fields to the surface energy are additive. We also find that there exists a kind of excitations related to the boundary string. 相似文献
146.
Chen GJ Qiao X Tian JL Xu JY Gu W Liu X Yan SP 《Dalton transactions (Cambridge, England : 2003)》2010,39(44):10637-10643
Two Eu(III) complexes, [Eu(acac)(3)(dpq)] (1) and [Eu(acac)(3)(dppz)] CH(3)OH (2) {viz. acetylacetonate (acac), dipyrido[3,2-d:20,30-f]quinoxaline (dpq), dipyrido[3,2-a:20,30-c] phenazine (dppz)}, have been synthesized and their DNA binding, photo-induced DNA cleavage activity and cell cytotoxicity are studied. The complexes display significant binding propensity to the calf thymus DNA in the order: 2(dppz) >1(dpq). Cleavage experiments using pBR322 supercoiled DNA suggest major groove binding for 2 and minor groove binding for 1. The mechanistic aspects on natural light (natural light in room during the day) and UV-A (365 nm) irradiation are via a mechanistic pathway involving formation of singlet oxygen and hydroxyl radical as the reactive species. The photo-induced DNA cleavage activity of 2 is also stronger than 1. The cytotoxicity of 1 and 2 against HeLa (cervical) cancer cells show that the IC(50) value of 19.11 ± 3.56 μM and 17.95 ± 5.47 μM, respectively. 相似文献
147.
Constructing a mutant strain of single gene disruption is the basis for the study of gene function and metabolomics. Systematic
and complete genome sequencing is the basis of genetic manipulation. In the case of a little knowledge about the Streptomyces lydicus genome and the speculation that polyketide synthases (type I) might be responsible for the polyketide side chain biosynthesis
of streptolydigin, a 588-bp fragment was amplified by polymerase chain reaction (PCR) according to the homology existing in
the same functional genes among Streptomyces. A mutant strain of this gene was constructed by single crossover homologous recombination. The results of sequence analysis
as well as the metabolite analysis of the mutant and the original strain by liquid chromatography/mass spectroscopy indicated
that this fragment was part of type II thioesterase (TE) gene, which was required for streptolydigin biosynthesis like other
type II TEs function in related antibiotics biosynthesis. Furthermore, targeted gene manipulation based on PCR was a powerful
tool for studying gene function and metabolomics, especially when little was known about the genomic sequence of streptomyces. 相似文献
148.
Kim T Lim S Kwon K Hong SH Qiao W Rhee CK Yoon SH Mochida I 《Langmuir : the ACS journal of surfaces and colloids》2006,22(22):9086-9088
Reported is the capacitive behavior of homogeneous and well-defined surfaces of pristine carbon nanofibers (CNFs) and surface-modified CNFs. The capacitances of the well-defined CNFs were measured with cyclic voltammetry to correlate the surface structure with capacitance. Among the studied pristine CNFs, the edge surfaces of platelet CNFs (PCNF) and herringbone CNFs were more effective in capacitive charging than the basal plane surface of tubular CNF by a factor of 3-5. Graphitization of PCNF (GPCNF) changed the edge surface of PCNF into a domelike basal plane surface, and the corresponding capacitances decreased from 12.5 to 3.2 F/g. A chemical oxidation of the GPCNF, however, recovered a clear edge surface by removal of the curved basal planes to increase the capacitance to 5.6 F/g. The difference in the contribution of the edge surface and basal-plane surface to the capacitance of CNF was discussed in terms of the anisotropic conductivity of graphitic materials. 相似文献
149.
Zhou J Chen M Qiao X Wu L 《Langmuir : the ACS journal of surfaces and colloids》2006,22(24):10175-10179
Organic-inorganic hybrid particles have many potential applications, but almost all of this research was focused on the hybrid particles containing one kind of inorganic nanoparticles. This paper presented a facile preparation method for SiO2/PS/TiO2 multilayer core-shell hybrid microspheres. In this approach, positively charged SiO2/PS core-shell hybrid particles were first synthesized by miniemulsion polymerization using cationic initiator and emulsifier. These positively charged SiO2/PS hybrid particles were mixed with tetra-n-butyl titanate for sol-gel reaction to directly form SiO2/PS/TiO2 multilayer core-shell hybrid microspheres. Some influencing parameters such as surfactant concentration, tetra-n-butyl titanate amount, and glacial acetic acid amount were investigated. TEM, TGA, and EDX analyses indicated that titania layers were successfully coated onto the surfaces of hybrid microspheres. 相似文献
150.
The surface tension of molten Sn-Bi (mole fraction X(Bi) = 0.455) alloy has been determined by the sessile drop method at oxygen partial pressure (P(O2)) of 1.0x10(-6) MPa and different temperatures. The experimental results have been analyzed and discussed, and the positive temperature coefficient of surface tension of molten Sn-Bi alloy has been elucidated. The surface tension of this molten alloy has also been obtained by calculation using STCBE based on Butler's equation and thermodynamic data. The experimental results agree well with the calculation values. 相似文献