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81.
硅/硅直接键合的界面杂质 总被引:4,自引:1,他引:3
用SIMS和扩展电阻测试研究了常规p~+/n和n~+/n硅/硅键合界面的杂质O,H,C,N,Fe,Ni以及掺杂原子B,P的行为。经1 100℃ 1小时键合后,界面的H消失;O,C,N稳定;重金属杂质Fe,Ni仍在界面附近;掺杂原子B,P的扩散小于2μm。 相似文献
82.
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
83.
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
84.
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
85.
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
86.
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
87.
88.
业务全面IP化、网络全面宽带化,成为这个时代的两大方向,并在省内干线传送网领域形成了富有激情的碰撞。“面向全IP业务的光传送网”显示出越来越明晰的框架,引领着最新的技术潮流。从未来来看,网络的IP化、扁平化不可逆转,省内干线传送网络最终会成为IP over Optical的架构。 相似文献
89.
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