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61.
The P2X7 receptor is a promising target for the treatment of various diseases due to its significant role in inflammation and immune cell signaling. This work describes the design, synthesis, and in vitro evaluation of a series of novel derivatives bearing diverse scaffolds as potent P2X7 antagonists. Our approach was based on structural modifications of reported (adamantan-1-yl)methylbenzamides able to inhibit the receptor activation. The adamantane moieties and the amide bond were replaced, and the replacements were evaluated by a ligand-based pharmacophore model. The antagonistic potency of the synthesized analogues was assessed by two-electrode voltage clamp experiments, using Xenopus laevis oocytes that express the human P2X7 receptor. SAR studies suggested that the replacement of the adamantane ring by an aryl-cyclohexyl moiety afforded the most potent antagonists against the activation of the P2X7 cation channel, with analogue 2-chloro-N-[1-(3-(nitrooxymethyl)phenyl)cyclohexyl)methyl]benzamide ( 56 ) exhibiting the best potency with an IC50 value of 0.39 μM.  相似文献   
62.
为总结出一套适合矿山实际的支护方案,二里河铅锌矿在矿山生产的20余年里,引进了多种支护工艺进行试验。矿山根据井巷、硐室所处工程环境,确定了锚杆、钢筋、钢架、混凝土进行单一或组合支护的方案,特别是千枚岩内12.4 m跨度的提升机硐室支护方式与参数,对矿山软弱岩层大跨度硐室工程支护具有参考价值。采场则按照急倾斜、缓倾斜矿体上盘千枚岩支护为例,分别列举了锚杆、锚杆+锚索支护的工程方案。采场联络巷、矿房行人通道等区域利用支柱+横梁临时支护。不但提高了采场作业安全性,也使采矿损失率降低5%,贫化率降低7%。  相似文献   
63.
《Ceramics International》2020,46(13):20974-20984
Photocatalytic technology is an environmentally safe method of eliminating organic pollutants and antibiotics in wastewater. In this research, the performance of Fe3O4/CdS/g-C3N4 (FCN) photocatalyst for degradation of antibiotics was studied. The composite photocatalysts with different concentrations of g-C3N4 were prepared. FCN has better photocatalytic activity than degradation dyes in removal of antibiotics under visible light. This indicates that FCN could effectively hinder the recombination of carriers, and the addition of g-C3N4 increases the optical response range of CdS. At the same time, the introduction of Fe3O4 magnetic nanoparticles overcomes the problem of difficulty in recovery of the powder photocatalyst. The photocatalytic activity is not reduced to any significant after three cycles of use.  相似文献   
64.
65.
The present study aimed to examine the antimicrobial activity of silkworm thorn (Cudrania tricuspidata) leaf extract (CTLE) and its application as a washing agent for fresh-cut romaine lettuce and kale. The antimicrobial activities of CTLE at various concentrations against Listeria monocytogenes were determined using disc diffusion and viable cell count assays, and CTLE exhibited strong inactivation of L. monocytogenes. In particular, after the treatment with 0.4% CTLE, the protein content of L. monocytogenes cells was significantly (P < 0.05) decreased from 507.21 to 254.58 μg mL−1, and damaged cells were observed by scanning electron microscopy. CTLE washing resulted in approximately 2-log reduction of microbial growth, similar to that of 0.01% NaOCl. In addition, CTLE washing did not affect the quality of romaine lettuce and kale. Therefore, these results suggest that CTLE is applicable as a new washing agent for inactivating L. monocytogenes on fresh-cut romaine lettuce and kale.  相似文献   
66.
采用水热法制备双钙钛矿催化剂Sr_2FeNiO_6,考察不同浓度KOH溶液(4 mol·L~(-1)、6 mol·L~(-1)、8 mol·L~(-1)、10 mol·L~(-1)、12 mol·L~(-1)、14 mol·L~(-1))对催化剂性能的影响,利用X射线衍射、比表面积测定、程序升温还原和扫描电镜等对样品进行性能表征,并以催化甲烷燃烧为目标,考察催化剂催化性能。结果表明,矿化剂KOH浓度对样品性能影响较大,当浓度为10 mol·L~(-1)时,起燃温度最低,T_(10%)为430℃;浓度为8 mol·L~(-1)时,样品比表面积最大,为19.0 m~2·g~(-1),完全燃烧温度最低,T_(90%)为610℃。  相似文献   
67.
Urban researchers have maintained a constant interest in the complexity and continuity of urban space usage. Some have applied actor–network theory (ANT) to investigate the heterogeneity of spaces and present them through the networks of their users’ activities. However, these accounts are predominantly limited in examining the extent to which these spaces may be heterogeneous when exploring such networks. This paper draws on recent ANT scholarship, which employs an ethnographic research conducted in a main park in a housing project at Dahiyat Al Hussein in Amman, Jordan. The findings describe the complex and unpredictable negotiations that occur within spaces by documenting the varieties and interrelations among user activity networks within this common and shared urban space. This research reveals the extent to which spaces, parks in this case, may be heterogeneous by unpacking their usage. The conclusions and insights assert the necessity of paying attention to design detail and creating designs that are responsive to evolving user activities.  相似文献   
68.
李春喜 《化工学报》2020,71(1):81-91
离子液体是近年来发展起来的一种绿色介质,在化工反应和分离过程中具有广泛的应用前景。离子液体的溶液热力学性质和相平衡数据是其相关工艺过程设计的基础。本文从如下几个方面综述了离子液体溶液热力学模型的研究进展,即溶液热力学研究方法、溶液热力学模型的构建、离子液体的结构和分子间作用力、离子液体的溶液热力学模型及其在相平衡计算中的应用。重点分析了适用于离子液体溶液热力学性质计算的状态方程模型和过量Gibbs自由能模型或活度系数模型,离子液体的电解质和非电解质溶液模型,以及这些模型对ILs结构、氢键和静电作用的处理方法。分析了这些模型的优缺点,并对今后离子液体的溶液热力学研究提出了建议。  相似文献   
69.
Exploring efficient and durable non-precious metal catalysts for oxygen reduction reaction (ORR) has long been pursued in the field of metal-air batteries, fuel cells, and solar cells. Rational design and controllable synthesis of desirable catalysts are still a great challenge. In this work, a novel approach is developed to tune the morphologies and structures of Fe–N–C catalysts in combination with the dual nitrogen-containing carbon precursors and the gas-foaming agent. The tailored Fe–N1/N2–C-A catalyst presents gauze-like porous nanosheets with uniformly dispersed tiny nanoparticles. Such architectures exhibit abundant Fe-Nx active sites and high-exposure surfaces. The Fe–N1/N2–C-A catalyst shows extremely high half-wave potential (E1/2, 0.916 V vs. RHE) and large limiting current density (6.3 mA cm−2), far beyond 20 wt% Pt/C catalyst for ORR. This work provides a facile morphological and structural regulation to increase the number and exposure of Fe-Nx active sites.  相似文献   
70.
TiO2 mesocrystals have been considered as an efficient photocatalyst due to the effective charge transport. Introducing hydroxyls in TiO2 is respected to reduce the energy barrier of hydrogen formation. Herein, a simple one-step fabrication of highly self-hydroxylated TiO2 mesocrystals (MCs) for enhancing photocatalytic hydrogen evolution is proposed. TiO2 single crystals (SCs), polycrystals (PCs) and MCs are obtained via regulating the pH of the precursor during hydrothermal treatment. Results indicate that the moderate alkaline condition is favorable for the synthesis of highly self-hydroxylated TiO2 MCs. Compared with SCs, PCs and commercial P25 TiO2 nanoparticles, MCs exhibit the best photocatalytic activity in H2 evolution. Specifically, the maximum hydrogen evolution rate under solar light illumination (22.8 mmol/h/g) is 10.5 times higher than that of P25. Moreover, the MCs exhibit excellent catalytic stability and the hydrogen evolution rate can be maintained at 20.8 mmol/h/g under solar illumination after five cycles of reactions. The highly self-hydroxylated TiO2 MCs are constructed from crystallographically oriented nanocrystals with abundant hydroxyls. The unique superstructure and large surface area of MCs enable the effective charge separation and transport. Moreover, the high density of hydroxyls can reduce the recombination rate of photo-generated free charges and energy barrier for hydrogen formation while facilitate light absorption. The synthesis of highly self-hydroxylated TiO2 MCs and the underlying mechanism offer interesting insights for modifying the structure and properties of TiO2 towards high-performance hydrogen evolution.  相似文献   
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