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91.
The paper is concerned with the development of hybrid-Trefftz (HT) p-element for nonlinear analysis of Reissner-Mindlin plates resting on an elastic foundation. The foundation may be of Winkler-type or Pasternak-type. Exact solutions of the Lame-Navier equations are used for the in-plane intraelement displacement field and an incremental form of the basic equations is adopted. With the aid of incremental form of these equations, all nonlinear terms may be taken as pseudo-loads. Moreover, some modifications have been made on the nonlinear boundary equations to simplify the ensuing derivation. As a result, the in-plane and out-of-plane equations are uncoupled, and then the derivation for the HT finite element (FE) formulation becomes very simple. The practical efficiency of the new element model has been assessed through several examples.  相似文献   
92.
邓舒鹏  黄文彬  刘永刚  刁志辉  彭增辉  姚丽双  宣丽 《物理学报》2012,61(12):126101-126101
首先制备了不同周期的染料掺杂全息液晶/聚合物光栅并进行激光抽运实验, 得到了激光器的调谐曲线,确定了激光器在574 nm到685 nm的谱带里均可以实现激光输出, 即激光器具有110 nm左右的可调谐范围. 之后, 通过温控仪控制样品的温度, 对周期为610 nm的染料掺杂全息液晶/聚合物光栅进行激光抽运, 探测不同温度下的输出激光光谱, 观察到随着温度由20℃升高到65℃, 激光器的中心波长由627.9 nm减小到623 nm, 产生了4.9 nm的波长蓝移.  相似文献   
93.
It has been shown that the smallest knots on the cubic lattice are all trefoils of length 24. In this paper, we show that the number of such unrooted knots on the cubic lattice is 3496.  相似文献   
94.
95.
Wang  Lujie  Wen  Xiaodong  Zhang  Xujun  Yuan  Shuntao  Xu  Qingbo  Fu  Feiya  Diao  Hongyan  Liu  Xiangdong 《Cellulose (London, England)》2021,28(9):5867-5879
Cellulose - In this article, carboxymethyl chitosan (CMC) and (3-carboxypropyl) trimethylammonium chloride (CPTC) were used as raw materials to prepare an antibacterial cotton fabric with excellent...  相似文献   
96.
Robust quantization watermarking with perceptual JND model has made a great success for image copyright protection. Generally, either restores each color channel separately or processes the vector representation from three color channels with the traditional monochromatic model. And it cannot make full use of the high correlation among RGB channels. In this paper, we proposed a robust quaternion JND Model for color image watermarking (QuatJND). In contrast to the existing perceptual JND models, the advantage of QuatJND is that it can integrate quaternion representation domain and colorfulness simultaneously, and QuatJND incorporates the pattern guided contrast masking effect in quaternion domain. On the other hand, in order to efficiently utilize the color information, we further develop a robust quantization watermarking framework using the color properties of the quaternion DCT coefficients in QuatJND. And the quantization steps of each quaternion DCT block in the scheme are optimal. Experimental results show that our method has a good performance in term of robustness with better visual quality.  相似文献   
97.
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   
98.
Xu WJ  Liao XJ  Xu SH  Diao JZ  Du B  Zhou XL  Pan SS 《Organic letters》2008,10(20):4569-4572
Galaxamide (1), a rare cyclic pentapeptide, was isolated from the marine algae Galaxaura filamentosa. A preliminary bioassay of Galaxamide showed remarkable in vitro antiproliferative activities against GRC-1 and HepG2 cell lines. The first total synthesis of the cyclic peptide was achieved for further biological evaluation.  相似文献   
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