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61.
重组家蚕核多角体病毒(rBmNPV)的复制及所载HuIFN-α基因的表达 总被引:3,自引:0,他引:3
报道了重组家蚕核多角体病毒(BombyxmorinuclearPolyhedrosisVirusBmNPV)在家蚕细胞BmN中复制的细胞病理学变化,除了不形成多角体以外,与野生型病毒相同.研究了病毒感染复数、细胞接种密度和细胞生长阶段对重组病毒复制和α-干扰素(IFN-α)表达量的影响.在一定低感染复数时,α-干扰素的产量较高.对于重组病毒的复制,最适的细胞接种密度为3.6~7.0×105细胞/瓶.在细胞指数生长前期(48~60h)接种重组病毒,对于获得较高的重组病毒复制效价和α-干扰素的产量都是有利的. 相似文献
62.
混合超图是含有两类超边的超图,一类称为C-超边,一类称为D-超边,它们的区别主要体现在染色要求上.混合超图的染色,要求每一C-超边至少有两个点染相同的颜色,而每一D-超边至少有两个点染不同的颜色.所用的最大颜色数称为对应混合超图的上色数,所用的最小颜色数称为对应混合超图的下色数.上、下色数与边数有密切关系.作者在文献[2]中证明了具有最小上色数的3一致C-超图边数的一个下界为‘n(n-2)/3’,其中n为对应混合超图的顶点数.该文证明当n=2k 1时,该下界是可以达到的. 相似文献
63.
采用甚高频等离子体增强化学气相沉积(VHF-PECVD)法,成功制备出从非晶到微晶过渡区 域的硅薄膜. 样品的微结构、光电特性及光致变化的测量结果表明这些处于相变域的硅薄膜 兼具非晶硅优良的光电性质和微晶硅的稳定性. 用这种两相结构的材料作为本征层制备了p- i-n太阳能电池,并测量了其稳定性. 结果在AM15(100mW/cm2) 的光强下曝光 800—5000min后,开路电压略有升高,转换效率仅衰退了29%.
关键词:
相变域硅薄膜
光电特性
太阳能电池 相似文献
64.
The co-transfection of p16(INK4a) and p14(ARF) genes into human lung cancer cell line A549 and the effects on cell growth and chemosensitivity 总被引:2,自引:0,他引:2
Xie QC Hu YD Wang LL Chen ZT Diao XW Wang ZX Guan HJ Zhu B Sun JG Duan YZ Chen FL Nian WQ 《Colloids and surfaces. B, Biointerfaces》2005,46(3):188-196
Two functionally and structurally different proteins, p16(INK4a) and p14(ARF), encoded by the gene INK4a/ARF located at 9p21 are cyclin-dependent kinase (cdk) inhibitors and important cell cycle regulators. More and more evidences have been accumulated to show that the exogenous p16(INK4a) or p14(ARF) can inhibit the cell growth and/or induce the apoptosis. But it is still unclear if they can play positive role when combine with the conventional chemotherapy in cancer treatment. Here we show that cationic liposome-mediated gene transfection of INK4a/ARF into lung cancer cell line A549, in which the INK4a/ARF locus was lost, suppressed the growth and induced apoptosis. When treated with five different chemotherapy drugs with different mechanism after the transfection, A549 got an increased chemosensitivity for adriamycin and cisplatin and an unchanged result for topotecan, taxol or vinorelbine. The results indicated that cell cycle redistribution and increased apoptosis index after transfection might be the main explanation for the enhanced chemosensitivity. The combination of gene therapy with conventional chemotherapy is not always better than single chemotherapy. This trial will be of benefit to the treatment of lung cancer when combine the conventional chemotherapy and gene therapy in the future. 相似文献
65.
Partitionally assembled organosulfur monolayers were prepared by using an electrochemically assisted assembly method on gold films that were preseparated into two regions insulated from each other. Cyclic voltammetry (CV) and X-ray photoelectron spectroscopy (XPS) were employed to characterize the n-dodecanethiol (DDT) and the 11-mercaptoundecanoic acid (MUA) monolayers, which were separately assembled on different substrate regions. CV results indicated that both the DDT- and MUA-coated gold electrodes showed a blocking property toward the negatively charged redox probe Fe(CN)6(3-). However, when positively charged Ru(NH3)6(3+) was used as the redox probe, the MUA- and DDT-modified electrodes showed quasireversible and blocking CV features, respectively. These phenomena were attributed to different interactions between the negatively charged MUA surface and the negatively or positively charged redox probes. XPS spectra obtained on the MUA modified region exhibited an O(1s) peak and a small discrete C(1s) peak, which arose from the oxygen and the carbon atoms in the carboxylic acid groups, respectively. For the DDT-modified region, these two peaks were absent. CV and XPS experimental results provided strong evidence that different SAMs were selectively deposited onto different regions of the preexisting patterns of the substrate by electrochemically partitioned assembly. The partitionally assembled sulfur-based monolayers with different terminal groups were used to form location-selective nanoparticle assemblies. This electrochemically partitioned assembly technique has great potential in controllable constructions of molecular layers and nanostructures on different surface microarchitectures that are closely integrated on one substrate but insulated from each other. 相似文献
66.
Monitoring canopy nitrogen status in winter wheat of growth anaphase with hyperspectral remote sensing 总被引:1,自引:0,他引:1
Biomass, leaf area index (LAI) and nitrogen status are important parameters for indicating crop growth potential and photosynthetic productivity in wheat. Nondestructive, quick assessment of leaf dry weight, LAI and nitrogen content is necessary for nitrogen nutrition diagnosis and cultural regulation in wheat production. In order to establish the monitoring model of nitrogen richness in winter wheat of growth anaphase, studying the relationship between the nitrogen richness (NR) containing nitrogen density, LAI and leaf dry weight and the difference of hyperspectral reflectance rates (deltaR), we conducted a comparable experiment with five winter wheat varieties under nitrogen application level of 0, 100, 200 and 400 kg x N x ha(-1). The results indicated the NRs of the different varieties of winter wheat leaves increased with increasing growth stage while in the different nitrogen levels it was sequenced as: NO>N3>N1>N2. Twelve vegetation indices were compared with corresponding NR. The NR had significantly negative correlation to TCARI and VD672 in those vegetation indices, and their correlations (r) arrived at 0.870 and 0.855, respectively. The coefficients of determination (R2) of two models were 0.757 and 0.731 by erecting model with the two indexes and NR Root mean square error (RMSE), relative error (RE) and determination coefficient between measured and estimated NR were employed to test the model reliability and predicting accuracy. Accuracy rates of the models based on TCARI and VD672 achieved 84.56% and 80.13%. The overall results suggested that leaf nitrogen status of growth anaphase in winter wheat has stable relationships with some vegetation indexes, especially index of TCARI and VD672. 相似文献
67.
In this paper, based on the theory of adjoint operators and dual norms, we define condition numbers for a linear solution function of the weighted linear least squares problem. The explicit expressions of the normwise and componentwise condition numbers derived in this paper can be computed at low cost when the dimension of the linear function is low due to dual operator theory. Moreover, we use the augmented system to perform a componentwise perturbation analysis of the solution and residual of the weighted linear least squares problems. We also propose two efficient condition number estimators. Our numerical experiments demonstrate that our condition numbers give accurate perturbation bounds and can reveal the conditioning of individual components of the solution. Our condition number estimators are accurate as well as efficient. 相似文献
68.
Huaian Diao Weiguo Wang Yimin Wei Sanzheng Qiao 《Numerical Linear Algebra with Applications》2013,20(1):44-59
In this paper, we investigate the normwise, mixed, and componentwise condition numbers and their upper bounds for the Moore–Penrose inverse of the Kronecker product and more general matrix function compositions involving Kronecker products. We also present the condition numbers and their upper bounds for the associated Kronecker product linear least squares solution with full column rank. In practice, the derived upper bounds for the mixed and componentwise condition numbers for Kronecker product linear least squares solution can be efficiently estimated using the Hager–Higham Algorithm. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
69.
Lactate derivatives are important synthetic precursors to a variety of pharmaceutical products. Previously reported methods to prepare lactates require multiple steps or have limited scopes. Herein, we report a Ni-catalyzed reductive addition of a variety of alkyl iodides to α-oxyacrylates to afford substituted lactates. Exploring the scope of radical acceptors reveals that electron-deficient alkenes, ranging from cyclohexenone to para-caboxystyrene, undergo efficient coupling with alkyl iodides. This method represents an alternative strategy access lactate derivatives. 相似文献