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31.
制备了四种不同结构的有机太阳能电池器件,器件1 ITO/LiF/PEDOT∶PSS/MEH-PPV/C60/Al、器件2 ITO/PEDOT∶PSS/MEH-PPV/C60/Al、器件3 ITO/LiF/PEDOT∶PSS/MEH-PPV∶C60/C60/Al和器件4 ITO/PEDOT∶PSS/MEH-PPV∶C60/C60/Al。测量了它们的电流-电压特性,结果显示在ITO和PEDOT∶PSS之间插入一薄层LiF使得器件性能得到较大提高。其器件1的JSC和FF比器件2的提高了74%和31%; 器件3的JSC比器件4的提高了约40%。这主要是由于LiF层有效地抑制了空穴向阳极的传输,并且LiF层在ITO和PEDOT:PSS之间形成了良好的界面特性。因此,这种结构上的改进有效地提高了有机太阳能电池的性能。 相似文献
32.
The main component of the Center for Genetic Engineering and Biotechnology(CIGB)candidate vaccine against Hepatitis C virus(HCV)is the pIDKE2 plasmid.The current designed downstream process for the production of pIDKE2 fulfils all regulatory requirements and renders the required quantities of pharmaceuticalgrade plasmid DNA(pDNA)with 95%purity.The advantages of this procedure include high plasmid purity and the elimination of undesirable additives,such as toxic organic extractants and animal-derived enzymes.However,yields and consequently the productivity of the process are low.Previous work demonstrated that the most critical step of the process is the reverse phase chromatography,where conventional porous particle resins are used.Therefore,to increase the process productivity,alternative technologies such as membranes and chromatographic monoliths were tested as alternative options for this critical step.Here,a comparison between the behaviors of CIM~ C4-HLD and Sartobind phenyl matrices was performed.To obtain higher productivities and purities,the dynamic binding capacities and selectivities were evaluated.The results showed that both matrices had a similar capacity for pIDKE2 plasmid,but the separation of pDNA isoforms using CIM~ technology was much better than that with Sartobind.Additionally,the optimal conditions for loading plasmid DNA on a CIMC4-HLD 800-mL monolithic column in a real production process were determined.These optimizations will allow production levels to satisfy the high plasmid consumption demanded by clinical trials. 相似文献
33.
Zhenliang Wu Yuwei Zhang John Zenghui Zhang Kelin Xia Fei Xia 《Journal of computational chemistry》2020,41(1):14-20
The development of ultracoarse-grained models for large biomolecules needs to derive the optimal number of coarse-grained (CG) sites to represent the targets. In this work, we propose to use the statistical internal cluster validation indexes to determine the optimal number of CG sites that are optimized based on the essential dynamics coarse-graining method. The calculated curves of Calinski-Harabasz and Silhouette Coefficient indexes exhibit the extrema corresponding to the similar CG numbers. The calculated ratios of the optimal CG numbers to the residue numbers of fine-grained models are in the range from 4 to 2. The comparison of the stability of index results indicates that Calinski-Harabasz index is the better choice to determine the optimal CG representation in coarse-graining. © 2019 Wiley Periodicals, Inc. 相似文献
34.
介绍了加速器驱动次临界系统(ADS)注入器Ⅱ束流聚焦单元超导螺线管的初步测试。 该测试在高度1 600 mm、 直径510 mm的垂直杜瓦中, 利用型号为cryogenic sms的超导电源对磁体进行了励磁, 并利用霍尔探头测试了其轴向磁场分布情况和漏场情况, 其中心磁场励磁后可达8.20 T, 漏场分布和计算值的相对误差小于10%。 同时, 对励磁过程中骨架的应力应变状态做了测试。 对测试结果的分析表明, 骨架结构设计合理, 应变状态变化平稳, 磁体低温稳定性能良好。The preliminary test of the superconducting solenoid for ADS injectorⅡhas been carried out in order to measure its performances. A vertical dewar with height 1 600 mm and outer diameter 510 mm was employed for this test. The magnet was energized by a cryogenic sms superconducting magnet current source. The axial magnetic distribution and leakage field were also tested through hall probes. The center field can be excited up to 8.20 T and the relative diviation between the measured value and the calculated value of the stray and leakage field is less than 10%. The measurements of the strain and stress status of the magnet skeleton show that the distortion is small and the mechanical performance is robust. 相似文献
35.
36.
高亮度1(1/2)超导腔光阴极注入器的腔形设计 总被引:1,自引:0,他引:1
对高亮度1 1/2超导腔光阴极注入器进行了腔形的概念研究设计。通过计算比较发现,重入腔的轴电场分布特性,使它很适合做超导光阴极注入器的首腔。我们还通过模拟计算,研究了电子束动力学各种参数的相互依赖关系,最后我们给出1 1/2腔的一组腔及束动力学参数。 相似文献
37.
A new method called spline convolution (SC) for resolving overlapped peaks was proposed in this paper. The differential pulse voltammetric overlapped peaks of mixtures of Pb(Ⅱ) and T1(I) were investigated by this method, and satisfactory results were obtained. The results show excellent correlation between peak areas of the processed signals and the concentrations. 相似文献
38.
Computer-aided interpretation of 13C-n.m.r. and i.r. spectra of organic molecules (m.w. ? 500) is done by an artificial intelligence approach. The output of the proposed ASSIGNER system is a list of functional groups which are reasonable candidates for the final structural isomers. The procedure of finding possible functional groups and the main features of the filtering steps are outlined. One search is worked out in detail to demonstrate the capability of the system. 相似文献
39.
L. Minkova E. Lefterova Ts. Koleva E. Nedkov M. Nikolova 《Colloid and polymer science》1988,266(10):898-905
Isotactic polypropylene films, Buplen Type, 40m thick, irradiated by a60Co source to doses 0.37–37 Mrad, are investigated by means of optical microscopy, WAXS, thermogravimetry, DSC and DTA. The original film exhibits a paracrystal structure. Irradiation does not change the films' structure. The kinetic parameters of the non-isothermal destruction and the thermodynamic parameters of melting are obtained. The samples irradiated to small doses (up to 3 Mrad) are thermally more stable; the activating energy of the destruction is higher than that of the original film. The temperature of melting slightly increases, while the enthalpy of melting decreases. For the range of doses of 3.7–37 Mrad, the films show low thermal stability and the destruction proceeds with low activating energy. From the results of the data obtained, the following assumptions are made: the-irradiation causes simultaneous crosslinking and chain scission at random sites along the chains. Fragments of partially crosslinked molecules and fractions of low molecular linear segments are formed. The destruction caused by radiation prevails above 3 Mrad. 相似文献
40.
L. Minkova 《Colloid and polymer science》1988,266(1):6-10
The melting and the crystallization of-irradiated (doses: 0–6Mrad) ultra-high molecular weight nascent polyethylene (UHMWPE) and high density nascent polyethylene with normal molecular weight (NMWPE) were investigated by DSC. The heat of melting of the nascent UHMWPE (DSC degree of crystallinity, respectively) increases up to a dose of 3 Mrad, after which it slightly decreases. The heat of the second melting of UHMWPE and of the first and second melting of NMWPE increases slightly up to a dose of 3 Mrad, after which it does not change. The X-ray degree of crystallinity of the nascent non-irradiated and irradiated polymers was 0.62±0.02. The calorimetric crystallinity was compared to the X-ray one. The results show that radiation does not affect the polymer crystallinity, but influences the thermodynamic heat of melting. The increase ofH
m vs. dose in UHMWPE is explained in terms of processes of tie molecule scission within the amorphous regions and on the surface of the crystals, which predominate over crosslinking up to a dose of 3 Mrad. That leads to an increase in the conformational mobility of the molecules and to an increase in the enthalpy, according to Peterlin's formula. The scission of the chains at the points of entangling of the tie molecules leads to a decrease in the temperature and to an increase in the enthalpy of crystallization of UHMWPE vs. dose. In NMWPE these effects are considerably weaker. 相似文献