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21.
Introduction As an important type of fungicides, triazole compounds are highly efficient, low poisonous and inward absorbent.1-3 At present, the studies on triazole derivatives are mainly concentrated on compounds with triazole as the only active group. The report of triazole compounds that contain both triazole group and other active group in a single molecule has rarely been found. Dialkyl-substituted dithiocarbamate salts have also shown interesting biological effects.4 N,N-Dialkyldithio-… 相似文献
22.
IntroductionTheincreasingcommercialvalueoftransitionmetalcomplexesofxanthateshasarousedconsiderableinterestintheirchemistry .Whiletheiranalyticalapplicationsarewellknown ,1theyarenowfindingextensiveuseinvulcan izationofrubber ,frothfloatationprocessforconcentrationofsulphideores ,asantioxidants ,lubricants ,2 ,3andhavebeenfoundtopossessfungicidalandinsecticidalactivi ties .4 Recently ,molecularrecognitionbetweenhostandguestmolecules ,inclusionphenomenaandnoncovalentmolecularinteractionarefunda… 相似文献
23.
1 INTRODUCTION Benzimidazole is an interesting heterocyclic compound because it is found in various naturally occurring drugs, such as omeprazole, astemizole and emedastine difumarate[1]. The efficacy of sub- stituted benzimidazoles in the treatment of parasitic infections is well known[2~4]. Substituted benzimid- azole moieties are established pharmacophores in parasitic chemotherapy. Bis(2-benzimidazole) and some substituted bis(benzimidazol-2-yl)alkanes have attracted much interest … 相似文献
24.
High molecular weight copoly(ether ketone)s (PEK) based on 4-(4-hydroxyphenyl)-1-phthalazinone (DHPZ)/4,4′-thiobisphenol (TBP)/4,4′-diflourodiphenylketone (DFK) were prepared by nucleophilic substitution polycondensation. The copolymers were characterized by FT- and ^1H-NMR. Thermal properties and solubility of copolymers were studied. 相似文献
25.
建立了单信道40Gbit/s归零-差分相移键控码(RZ-DPSK)传输系统模型,详细地分析并比较了线性相位噪声和非线性相位噪声对系统性能的影响。结果表明,由放大器自发辐射(ASE)噪声带来的线性相位噪声对传输系统的性能影响最大,ASE与自相位调制(SPM)相互作用引起的Gordon-Mollenauer(G-M)相移次之,带内四波混频(IFWM)的影响最小。在最优输入功率的条件下,由ASE带来的线性相位噪声引起的系统差分相位Q值代价大于204dB,由G-M相移引起的系统差分相位Q值代价小于7.5dB。仿真结果表明,对于采用掺铒光纤放大器(EDFA)级联放大的单信道40Gbit/s RZ-DPSK传输系统,ASE噪声是限制系统无中继传输距离的最主要因素。 相似文献
26.
27.
Ben Li Yumeng Ji Chenlong Yi Xufeng Wang Chaoyang Liu Chufan Wang Xiaohu Lu Xiaohan Xu Xiaowei Wang 《Molecules (Basel, Switzerland)》2022,27(13)
Atherosclerosis (AS) is one of the leading causes of death among the elderly, and is primarily caused by foam cell generation and macrophage inflammation. Rutin is an anti-inflammatory, anti-oxidant, anti-allergic, and antiviral flavonoid molecule, known to have anti-atherosclerotic and autophagy-inducing properties, but its biological mechanism remains poorly understood. In this study, we uncovered that rutin could suppress the generation of inflammatory factors and reactive oxygen species (ROS) in ox-LDL-induced M2 macrophages and enhance their polarization. Moreover, rutin could decrease foam cell production, as shown by oil red O staining. In addition, rutin could increase the number of autophagosomes and the LC3II/I ratio, while lowering p62 expression. Furthermore, rutin could significantly inhibit the PI3K/ATK signaling pathway. In summary, rutin inhibits ox-LDL-mediated macrophage inflammation and foam cell formation by inducing autophagy and modulating PI3K/ATK signaling, showing potential in treating atherosclerosis. 相似文献
28.
As an important part of satellite communication network, LEO satellite constellation network is one of the hot research directions. Since the nonuniform distribution of terrestrial services may cause inter-satellite link congestion, improving network load balancing performance has become one of the key issues that need to be solved for routing algorithms in LEO network. Therefore, by expanding the range of available paths and combining the congestion avoidance mechanism, a load balancing routing... 相似文献
29.
Xiaohu Ge Jinzhong Hu Cheng-Xiang Wang Chan-Hyun Youn Jing Zhang Xi Yang 《Mobile Networks and Applications》2012,17(1):29-35
In this paper, the energy efficiency of multi-input single-output and orthogonal frequency division multiplexing (MISO-OFDM)
communication systems with power and capacity constraints is investigated. By formulating the power allocation problem of
MISO-OFDM communication systems, the minimum subchannel transmission power is analyzed with power and capacity constraints.
Simulation results indicate that there exists a specific minimum subchannel capacity threshold. Moreover, the energy efficiency
of MISO-OFDM communication systems starts to increase only when the minimum subchannel capacity exceeds the specific threshold. 相似文献
30.