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排序方式: 共有6087条查询结果,搜索用时 62 毫秒
1.
Science China Mathematics - This paper studies exact synchronization and asymptotic synchronization problems for a controlled linear system of ordinary differential equations. In this paper, we... 相似文献
2.
《中国化学快报》2022,33(12):5111-5115
A stimuli-responsive supramolecular polymer network has been constructed based on the host-guest interactions between the copolymer poly-P[5]A with pendent pillararene units and bis(sulfonium) diction guest G2. The formation mechanism of the supramolecular polymer network has been explored by the intensive study. With the addition of the competitive molecules and heating, the supramolecular polymer network could be dissociated and lead to clear changes in NMR spectroscopy and viscosity property. 相似文献
3.
BIT Numerical Mathematics - In this paper, we introduce a novel class of embedded exponential-type low-regularity integrators (ELRIs) for solving the KdV equation and establish their optimal... 相似文献
4.
带滩槽地形的连续弯道中纵向流速横向分布解析 总被引:1,自引:0,他引:1
本文基于沿水深积分的动量方程,假定二次流项和弯道附加应力项沿横断面呈线性分布,提出了预测弯道垂线平均纵向流速的解析计算方法,进一步提出了河槽区和河滩区垂线平均纵向流速沿断面分布的求解模式,并将其应用于带滩槽地形的反向连续弯道水槽中. 根据实测数据率定计算参数,该模式可计算不同出口水深条件下断面垂线平均纵向流速分布,计算结果与实测数据吻合良好.分析了线性分布假设中参数随水深变化的取值规律和沿横断面分布特点,并对参数进行了敏感性分析,分析表明线性假设中一次项系数分区位置对流速峰值的大小和位置影响较大,常数项根据地形横比降变化进行分区取值,流速计算值对常数项在水平段和斜坡段分区位置较为敏感,并根据参数的敏感度提出了参数沿水槽的均值作为参考值.讨论了动量方程中二次流项和弯道附加应力项沿弯道的横向分布规律,进一步认识线性假设的适用范围,结果表明线性假设在本文试验水槽中适用于弯道沿程.研究成果有助于认识带滩槽地形的连续弯道纵向流速分布特征及其形成机制. 相似文献
5.
This paper is concerned with the Cauchy problem on the Boltzmann equation without angular cutoff assumption for hard potential in the whole space. When the initial data is a small perturbation of a global Maxwellian, the global existence of solution to this problem is proved in unweighted Sobolev spaces with . But if we want to obtain the optimal temporal decay estimates, we need to add the velocity weight function, in this case the global existence and the optimal temporal decay estimate of the Boltzmann equation are all established. Meanwhile, we further gain a more accurate energy estimate, which can guarantee the validity of the assumption in Chen et al. (0000). 相似文献
6.
7.
Chen Fenge Li Bing Peng Xingchun 《Methodology and Computing in Applied Probability》2022,24(2):635-659
Methodology and Computing in Applied Probability - This paper is devoted to the study of an optimal investment and risk control problem for an insurer. The risky asset process and the insurance... 相似文献
8.
《中国化学快报》2022,33(8):3772-3776
RNA molecules contain diverse modifications that display important functions in a variety of physiological and pathological processes. So far over 150 chemical modifications have been characterized to be present in various RNA species, such as in messenger RNA (mRNA), ribosomal RNA (rRNA), and transfer RNA (tRNA). Previous studies revealed that certain RNA modifications were correlated to specific human diseases, indicating RNA modifications could serve as the potential indicator of human diseases. However, systemic investigation of the alteration of RNA modifications in different RNA species of carcinoma tissues are still lacked. Herein, we carried out the comprehensive profiling and evaluation of the alteration of RNA modifications in thyroid carcinoma by liquid chromatography-tandem mass spectrometry (LC-ESI-MS/MS) analysis. The developed method allowed us to simultaneously detect 48 different types of RNA modifications. Using this method, we detected 10, 15, 14, and 25 modifications in mRNA, 18S rRNA, 28S rRNA and small RNA (< 200 nt), respectively. Compared to the normal tissues, we revealed a total of 14 RNA modification exhibited significant increase and 2 RNA modifications showed significant decrease in thyroid carcinoma tissues. Our study provided the first comprehensive profile as well as the alteration of modifications in different RNA species in thyroid carcinoma and matched tumor-adjacent normal tissues. The altered pattern RNA modifications may serve as the indicator of thyroid carcinoma. Moreover, this study may promote the in-depth understanding of the regulatory roles of RNA modifications in thyroid carcinoma. 相似文献
9.
Dr. Wenyan Hao Yuchen Sha Dr. Yi Deng Yi Luo Li Zeng Shan Tang Dr. Yue Weng Prof. Dr. Chien-Wei Chiang Prof. Dr. Aiwen Lei 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(19):4931-4934
An in situ generated oxidation species of nickel quinolinylpropioamide intermediate was produced. Characterization by X-ray absorption near edge structure (XANES) and EPR provides complementary insights into this oxidized nickel species. With aliphatic amides and isocyanides as substrates, a nickel-catalyzed facile synthesis of structurally diverse five-membered lactams could be achieved. 相似文献
10.
Wu WanQing Cai QingYu Wu ShuoMei Zhang HuanGuo 《International Journal of Theoretical Physics》2019,58(6):1854-1860
Recently, Ye et al. (Int. J. Theor. Phys. 56, 1517–1529, 2017) proposed a quantum private comparison (QPC) protocol based on five-qubit entanglement state. Two parties can verify that their secret information is equal or not with the help of the semi-honest third party (TP). However, in this paper we will point out the Ye et al.’s initial protocol is not safe under a special participant attack. That is a malicious participant can get the other party’s secret input information illegally under the forgery attack. Furthermore, we give two possible improvement protocols, which can perform this protocol secure against this kind of attack.
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