微腔中两原子缀饰态的二光子衰变

研究了微腔中原子衰变问题。考虑微腔中存在两个原子，两原子与腔场强耦合形成的缀饰原子与腔壁相互作用在特定初始条件下的衰变问题，指出在腔场中该衰变方式下，腔场光子数越多、衰变则越强     

Martensitic transformation in Mn–Ni–Sn Heusler alloys

Three magnetic shape memory alloys: Mn₅₀Ni_50−x Sn _x (x = 5, 7.5, and 10) were produced as bulk polycrystalline ingots by arc melting. The structural austenite–martensite transformation was checked by calorimetry. The transformation temperatures decrease as increasing the Sn content. The same trend is found in the entropy and enthalpy changes related to the transformation. The control of the valence electron by atom e/a determines the transformation temperatures range in this kind of alloys and it is possible to develop alloys that can be candidates in applications as sensors and actuators. Furthermore, X-ray diffraction was performed to check the crystalline structure at room temperature.     

Adsorptive refolding of a highly disulfide-bonded inclusion body protein using anion-exchange chromatography

α-Fetoprotein (AFP) is a prospective biopharmaceutical candidate currently undergoing advanced-stage clinical trials for autoimmune indications. The high AFP expression yields in the form of inclusion bodies in Escherichia coli renders the inclusion body route potentially advantageous for process scale commercial manufacture, if high-throughput refolding can be achieved. This study reports the successful development of an ‘anion-exchange chromatography’-based refolding process for recombinant human AFP (rhAFP), which carries the challenges of contaminant spectrum and molecule complexity. rhAFP was readily refolded on-column at rhAFP concentrations unachievable with dilution refolding due to viscosity and solubility constraints. DEAE-FF functioned as a refolding enhancer to achieve rhAFP refolding yield of 28% and product purity of 95% in 3 h, at 1 mg/ml protein refolding concentration. Optimization of both refolding and chromatography column operation parameters (i.e. resin chemistry, column geometry, redox potential and feed conditioning) significantly improved rhAFP refolding efficiency. Compared to dilution refolding, on-column rhAFP refolding productivity was 9-fold higher, while that of off-column refolding was more than an order of magnitude higher. Successful demonstration that a simple anion-exchange column can, in a single step, readily refold and purify semi-crude rhAFP comprising 16 disulfide bonds, will certainly extend the application of column refolding to a myriad of complex industrial inclusion body proteins.     

James空间的推广

R.H.Lohman和P.G.Casazza[2]就自反的、具有对称的块P——Hilbert基的Banach空间进行了讨论,给出了一阶次自反Banach空间的一种构造方法。本文在一类具有IS型基的Banach空间上进行了推广,并给出了构造一阶次自反空间的更一般性的方法。 以下记号S、的意义同[2],文中IS序列、ESA序列、SA序列及单调基、正规基的定义可见[2]、[3]。并总设E是Banach空间,{x_i}是E之IS型单调正规基。 一般的James空间定义类似[2],区别在于对于a=(a_i)∈S和我们定义:     

高压下聚苯胺系高分子导体电学特性的研究

 本文研究了大共轭π键结构的聚苯胺等高聚物在高压下的电学性能，其结果表明PAn-H⁺的电阻值在p=3.2 GPa下出现极小值，可作3.2 GPa压力下的定标物质。并指出聚苯胺系列导体属于电子性导电物质，而且在不同的压力条件下电流和电压的关系均表现为非线性。     

Scanning tunnelling microscopy study of a columnar metallomesogen: bis(β-diketonato)palladium(II) complexes on graphite

Scanning tunnelling microscopy is used to analyse the structure of the columnar metallomesogen bis[1-(3',4',5'-trioctyloxyphenyl)-3-(4'-octyloxphenyl)prop [Pd(II)BPOC8], on the basal plane of highly oriented pyrolytic graphite. It is observed with near molecular level resolution that adsorbed molecules form a regular two-dimensional (2D) arrangement on the surface. The intermolecular spacing in the 2D crystallization is significantly shorter than in the intercolumnar mesophase, indicating that the alkyl chains of adjacent molecules interdigitate. Change in the carbon length of alkyl side chain groups results in a change in molecular periodicity in the 2D crystal. Models for the unit cell are proposed based on computer simulation.     

Global stability of a three-dimensional bio-reactor with inhibition responses

A three-dimensional bio-reactor model of exploitative competition of two predator organisms with inhibition responses for the same renewable organism with reproductive properties is considered. By constructing a modified Lyapunov function and using LaSalle’s invariant principle, it is shown that the lower “break-even” concentration predator organism survives in the competition.      

Poly(N‐vinylcarbazole) chemically modified graphene oxide

A new soluble donor‐acceptor type poly(N‐vinylcarbazole)‐covalently functionalized graphene oxide (GO‐PVK) has been synthesized by reaction of DDAT (S‐1‐dodecyl‐S′‐(α,α′‐dimethyl‐α″‐aceticacid)trithiocarbonate)‐PVK with GO‐toluene‐2,4‐diisocynate. The incorporation of sufficient amount of PVK chains makes the modified GO nanosheets readily dispersible in organic solvents. The resulting material exhibits an enhanced solubility of 10 mg/mL in organic solvents. Covalent grafting of PVK onto the edge and surface of GO nanosheets did not change the carbazole absorption in the ultraviolet region, but substantially reduced the absorption intensity of GO in the visible region. The intensity of the emission band of GO‐PVK at 437 nm was a little bit quenched when compared with that of DDAT‐PVK, suggesting intramolecular quenching from PVK to GO. Such intramolecular quenching process may involve energy or electron transfer between the excited singlet states of the PVK moiety and the GO moiety. The HOMO/LUMO values and the energy bandgap of GO‐PVK experimentally estimated by the onset of the redox potentials are ?5.60, ?3.58, and 2.02 eV, respectively. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 2642–2649, 2010     

Na3AlF6-Al2O3熔盐体系中ZnFe2O4基阳极的电化学行为

研究了ＺｎＦｅ２Ｏ４基阳极在Ｎａ３ＡｌＦ６－Ａｌ２Ｏ３熔盐体系中的电化学稳定性，讨论了电极的析氧历程并得到了析氧过电位与阳极表观电流密度之间的Ｔａｆｅｌ关系式，η＝０．１２＋０．０５２ｌｏｇｉ（ｉ＝０．０１５－０．４４Ａ／ｃｍ＾２）用三角波电位扫描法测定了电极析氧过程的伏安曲线。