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排序方式: 共有219条查询结果,搜索用时 15 毫秒
1.
Zhu  Min  Li  Jun-ping  Liu  De-zhi 《应用数学学报(英文版)》2021,37(3):617-627
Acta Mathematicae Applicatae Sinica, English Series - So far there have been few results presented on the exponential stability for time-changed stochastic differential equations. The main aim of...  相似文献   
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Journal of Sol-Gel Science and Technology - Zinc oxide (ZnO) and cobalt (Co)-ZnO nanocomposites were first reacted with 2-Methylimidazole to synthesize the zeolitic imidazole frameworks as...  相似文献   
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In this paper, we prove that two-parameter Volterra multifractional process can be approximated in law in the topology of the anisotropic Besov spaces by the family of processes{B_n(s,t)},n∈N defined by B_n(s,t)=∫_0~s ∫_0~tk_(a(s))(s,u)K_(β(t))(t,u)θ_(n(u,v))dudv,here {θ_n(u, v)}n∈N is a family of processes, converging in law to a Brownian sheet as n→∞,based on the well known Donsker's theorem.  相似文献   
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Nasopharyngeal carcinoma (NPC) is a common malignant head and neck tumor. Drug resistance and distant metastasis are the predominant cause of treatment failure in NPC patients. Hispidulin is a flavonoid extracted from the bioassay-guided separation of the EtOH extract of Salvia plebeia with strong anti-proliferative activity in nasopharyngeal carcinoma cells (CNE-2Z). In this study, the effects of hispidulin on proliferation, invasion, migration, and apoptosis were investigated in CNE-2Z cells. The [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] (MTT) assay and the colony formation assay revealed that hispidulin could inhibit CNE-2Z cell proliferation. Hispidulin (25, 50, 100 μM) also induced apoptosis in a dose-dependent manner in CNE-2Z cells. The expression of Akt was reduced, and the expression of the ratio of Bax/Bcl-2 was increased. In addition, scratch wound and transwell assays proved that hispidulin (6.25, 12.5, 25 μM) could inhibited the migration and invasion in CNE-2Z cells. The expressions of HIF-1α, MMP-9, and MMP-2 were decreased, while the MMPs inhibitor TIMP1 was enhanced by hispidulin. Moreover, hispidulin exhibited potent suppression tumor growth and low toxicity in CNE-2Z cancer-bearing mice at a dosage of 20 mg/kg/day. Thus, hispidulin appears to be a potentially effective agent for NPC treatment.  相似文献   
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以三氟乙酰丙酮(tfac)为共配体的稀土配合物分别与5-溴-2-羟基苯取代的自由基配体和5-硝基-2-羟基苯取代的自由基配体进行反应,合成3个稀土-自由基配合物[Ln2(tfac)4(NIT-5Br-2PhO)2](Ln=Gd (1),Dy (2))和[Dy2(tfac)4(NIT-5NO2-2PhO)2](3)(NIT-5Br-2PhOH=2-(2′-hydroxy-5′-bromophenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide,NIT-5NO2-2PhOH=2-(2′-hydroxy-5′-nitrophenyl)-4,4,5,5-tetra-methylimidazoline-1-oxyl-3-oxide)。单晶结构分析表明这3个化合物中的稀土离子均通过自由基配体上的羟基氧基团连接为双核的结构。配合物1的直流磁化率表征揭示了Gd(Ⅲ)离子间的反铁磁耦合对其磁行为起主要作用。  相似文献   
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Bai  Lei  Ge  Lili  Gu  Junjiu  Fang  Lu  Li  Shaojun 《Journal of Sol-Gel Science and Technology》2021,99(1):211-219
Journal of Sol-Gel Science and Technology - Zeolitic Imidazolate Framework (ZIF-8) micropolyhedra were employed as a raw material for the synthesis of fine cadmium sulfide/zinc sulfide (CdS/ZnS)...  相似文献   
8.
本文以龙井水库大坝为例,运用有限单元法对粘土心墙坝的渗流进行分析计算,同时运用瑞典圆弧滑动法和简化Bishop法对粘土心墙坝的坝体稳定进行分析计算,在此基础上对水库大坝进行了渗流安全评价和稳定性安全评价。  相似文献   
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Extra-large-pore zeolites for processing large molecules have long been sought after by both the academia and industry. However, the synthesis of these materials, particularly extra-large-pore pure silica zeolites, remains a big challenge. Herein we report the synthesis of a new extra-large-pore silica zeolite, designated NUD-6, by using an easily synthesized aromatic organic cation as structure-directing agent. NUD-6 possesses an intersecting 16×8×8-membered ring pore channel system constructed by four-connected (Q4) and unusual three-connected (Q3) silicon species. The organic cations in NUD-6 can be removed in nitric acid to yield a porous material with high surface area and pore volume. The synthesis of NUD-6 presents a feasible means to prepare extra-large pore silica zeolites by using assembled aromatic organic cations as structure-directing agents.  相似文献   
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