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Design, synthesis and HIV-RT inhibitory activity of novel thiazolidin-4-one derivatives

Hua CHEN, Zaihong GUO, Qingmei YIN, Xiaoxu DUAN, Yunjing GU, Xiaoliu LI

《化学科学与工程前沿(英文)》 2011年 第5卷 第2期   页码 231-237 doi: 10.1007/s11705-010-1022-7

摘要: A series of 2-aryl-3-(4,5,6-trimethylpyrimidin-2-yl) thiazolidin-4-ones ( – ) and their derivatives bearing a lipophilic substituent, like acetoxy group ( – ), propionyloxy group ( – ), methyl ( and ) at C-5 on thiazolidin-4-one ring were designed, synthesized and evaluated for their HIV-RT inhibitory activity. Using self-catalyzed Pummerer reaction, compounds – and – were obtained in good yield (63.1% 75.2%). Preliminary anti-HIV-RT test of these derivatives indicated that compounds – , (propionyloxy group at C-5) showed moderate HIV-RT inhibitory activity and compounds and with methyl at C-5 showed a weak HIV-RT inhibitory activity. Structure activity relationship analysis suggested that the substituted groups on C-5 would be unfavorable to anti-HIV-RT activity and that the steric effect might play a critical role in the anti-HIV RT activity.

关键词: 5-subsituted thiazolidin-4-ones     Pummerer reaction     anti-HIV-RT activity     SARs    

Microwave-assisted synthesis and antimicrobial activities of 2-aryl-3-(naphthalene-1 or 2-yl)-1,3-thiazolidin-4-ones

Hua CHEN, Yanan LI, Jie BAI, Lian ZHAO, Xiangguo YUAN, Xiaoliu LI, Keqiang CAO

《化学科学与工程前沿(英文)》 2009年 第3卷 第2期   页码 186-191 doi: 10.1007/s11705-009-0004-0

摘要: 2-aryl-3-(naphthalene-1 or 2-yl)-1,3-thiazolidin-4-ones and were synthesized in 41%-67% yield by using microwave-assisted one-pot protocol. The structures of the new compounds , , , , , , and - were confirmed by IR, NMR, MS, and elemental analysis. The antimicrobial activities of the compounds against pv. lachrymans (Smith et Bryan) Young, Dye & Wilkie, Pers., and Blum. were examined. Some of the compounds showed good antifungical activity against Blum.

关键词: microwave-assisted synthesis     naphthyl     thiazolidin-4-one     antimicrobial    

Dechlorination of 2,2′,4,4′,5,5′-hexachlorobiphenyl by thermal reaction with activated carbon-supported

Yifei SUN, Xin FU, Wei QIAO, Wei WANG, Tianle ZHU, Xinghua LI

《环境科学与工程前沿(英文)》 2013年 第7卷 第6期   页码 827-832 doi: 10.1007/s11783-013-0543-y

摘要: Activated carbon (AC)-supported copper or zinc made from ion exchange resin (IRCu-C and IRZn-C) have an increased metal load of 557.3 mg?g and 502.8 mg?g compared to those prepared by the traditional method involving impregnation with AC and copper (II) citrate or zinc citrate solution (LaCu-C and LaZn-C) of 12.9 mg?g and 46.0 mg?g respectively. When applied to decompose 2,2′,4,4′,5,5′-hexachlorobiphenyl at 250 °C, IRCu-C achieved higher activity of 99.0% decomposition efficiency than LaCu-C of 84.7%, IRZn-C of 90.5% and LaZn-C of 62.7%. When the reaction temperature rose to 350 °C, all the four kinds of reactants can decompose PCB-153 with efficiency above 90%. Further, X-ray photoelectron spectroscopy characterization of IRCu-C before and after the reaction indicated transformation of 19.1% of Cu atoms into Cu , illustrating that Cu is the active ingredient or electron donor promoting the decomposition of PCB-153. The mechanism underlying this process differs from a traditional H donor. However, there is no significant change on the surface of IRZn-C before and after the reaction, suggesting that Zn acts as catalyst during the process of PCB-153 decomposition.

关键词: polychlorinated biphenyls     activated carbon-supported copper or zinc     dechlorination     electron donor    

5′-tiRNA-Gln inhibits hepatocellular carcinoma progression by repressing translation through the interactionwith eukaryotic initiation factor 4A-I

《医学前沿(英文)》 2023年 第17卷 第3期   页码 476-492 doi: 10.1007/s11684-022-0966-6

摘要: tRNA-derived small RNAs (tsRNAs) are novel non-coding RNAs that are involved in the occurrence and progression of diverse diseases. However, their exact presence and function in hepatocellular carcinoma (HCC) remain unclear. Here, differentially expressed tsRNAs in HCC were profiled. A novel tsRNA, tRNAGln-TTG derived 5′-tiRNA-Gln, is significantly downregulated, and its expression level is correlated with progression in patients. In HCC cells, 5′-tiRNA-Gln overexpression impaired the proliferation, migration, and invasion in vitro and in vivo, while 5′-tiRNA-Gln knockdown yielded opposite results. 5′-tiRNA-Gln exerted its function by binding eukaryotic initiation factor 4A-I (EIF4A1), which unwinds complex RNA secondary structures during translation initiation, causing the partial inhibition of translation. The suppressed downregulated proteins include ARAF, MEK1/2 and STAT3, causing the impaired signaling pathway related to HCC progression. Furthermore, based on the construction of a mutant 5′-tiRNA-Gln, the sequence of forming intramolecular G-quadruplex structure is crucial for 5′-tiRNA-Gln to strongly bind EIF4A1 and repress translation. Clinically, 5′-tiRNA-Gln expression level is negatively correlated with ARAF, MEK1/2, and STAT3 in HCC tissues. Collectively, these findings reveal that 5′-tiRNA-Gln interacts with EIF4A1 to reduce related mRNA binding through the intramolecular G-quadruplex structure, and this process partially inhibits translation and HCC progression.

关键词: EIF4A1     G-quadruplex     hepatocellular carcinoma     tRNA-derived small RNA     translation initiation    

On the monolayer dispersion behavior of Co3O4 on HZSM-5 support: designing applicable

《化学科学与工程前沿(英文)》 2023年 第17卷 第11期   页码 1741-1754 doi: 10.1007/s11705-023-2332-x

摘要: Based on monolayer dispersion theory, Co3O4/ZSM-5 catalysts with different loadings have been prepared for selective catalytic reduction of nitrogen oxides by ammonia. Co3O4 can spontaneously disperse on HZSM-5 support with a monolayer dispersion threshold of 0.061 mmol 100 m–2, equaling to a weight percentage around 4.5%. It has been revealed that the quantities of surface active oxygen (O2) and acid sites are crucial for the reaction, which can adsorb and activate NOx and NH3 reactants effectively. Below the monolayer dispersion threshold, Co3O4 is finely dispersed as sub-monolayers or monolayers and in an amorphous state, which is favorable to generate the two kinds of active sites, hence promoting the performance of ammonia selective catalytic reduction of nitrogen oxide. However, the formation of crystalline Co3O4 above the capacity is harmful to the reaction performance. 4% Co3O4/ZSM-5, the catalyst close to the monolayer dispersion capacity, possesses the most abundant active O2 species and acidic sites, thereby demonstrating the best reaction performance in all the samples. It is proposed the optimal Co3O4/ZSM-5 catalyst can be prepared by loading the capacity amount of Co3O4 onto HZSM-5 support.

关键词: Co3O4/ZSM-5     NOx-SCR by NH3     monolayer dispersion threshold effect     surface acid sites     surface active O2 anions    

Facile controlled synthesis of hierarchically structured mesoporous Li4Ti5O12/C/rGO composites as high-performance

Cehuang FU, Shuiyun SHEN, Ruofei WU, Xiaohui YAN, Guofeng XIA, Junliang ZHANG

《能源前沿(英文)》 2022年 第16卷 第4期   页码 607-612 doi: 10.1007/s11708-021-0798-0

摘要: In this paper, a facile strategy is proposed to controllably synthesize mesoporous Li4Ti5O12/C nanocomposite embedded in graphene matrix as lithium-ion battery anode via the co-assembly of Li4Ti5O12 (LTO) precursor, GO, and phenolic resin. The obtained composites, which consists of a LTO core, a phenolic-resin-based carbon shell, and a porous frame constructed by rGO, can be denoted as LTO/C/rGO and presents a hierarchical structure. Owing to the advantages of the hierarchical structure, including a high surface area and a high electric conductivity, the mesoporous LTO/C/rGO composite exhibits a greatly improved rate capability as the anode material in contrast to the conventional LTO electrode.

关键词: Li4Ti5O12     phenolic-resin-based carbon     mesoporous composite     graphene    

UI图层合并器:基于计算机视觉与边界先验的UI图层合并方法 Research Article

陈云农1,5,甄焱鲲4,施楚宁2,李佳智2,陈柳青2,3,5,李泽健1,3,5,孙凌云2,3,5,周婷婷4,常艳芳4

《信息与电子工程前沿(英文)》 2023年 第24卷 第3期   页码 373-387 doi: 10.1631/FITEE.2200099

摘要: 随着互联网行业图形用户界面(GUI)开发工作量的快速增长,国内外学者试图从GUI图片生成可维护的前端代码。该任务更适合从包含有用户界面元数据的UI设计稿来实现代码生成。然而,碎片图层不可避免地会出现在UI设计稿中,这大大降低了生成代码的质量。目前尚未有自动化GUI技术来检测并合并碎片图层以提高生成代码的可维护性。本文提出UI图层合并器(UILM),一种基于计算机视觉的方法,可以自动检测并合并碎片图层为完整的UI组件。本文提出的UILM包含合并区域检测器和碎片图层合并算法。合并区域检测器结合边界先验知识来准确地检测出UI组件的边界。基于此,碎片图层合并算法可以搜索出边界内的相关碎片层并将其合并为整体。此外,我们提出一种动态数据增强算法来提高合并区域检测器的性能。我们还构建了用于训练合并区域检测器和测试UILM的大规模UI数据集。实验结果表明,本文提出的方法在合并区域检测方面优于最佳基线,并达到了有效的图层合并准确率。最后,对真实应用程序的用户研究也证实了本文方法的有效性。

关键词: 用户界面(UI)生成代码;UI设计规范;UI碎片图层合并;目标检测    

新闻媒体眼中的中国:新冠肺炎疫情下的案例研究 Research Article

黄宏1,2,3,4,陈哲学1,2,3,4,石宣化1,2,3,4,王晨旭1,2,3,4,何泽鹏1,2,3,4,金海1,2,3,4,张明新5,李宗亚5

《信息与电子工程前沿(英文)》 2021年 第22卷 第11期   页码 1443-1457 doi: 10.1631/FITEE.2000689

摘要: 例如,新冠肺炎疫情期间,国际媒体更加关注中国民生;在3月和4月,“中国疫苗进展”“特定药物和治疗”“美国病毒爆发”成为媒体最常见话题;在新闻态度方面,古巴、马来西亚、委内瑞拉对中国持正面态度,而法国、加拿大

关键词: 国家形象;新冠肺炎;主题挖掘;实体;新闻立场;情感    

Metabolic uncoupler, 3,3′,4′,5-tetrachlorosalicylanilide addition for sludge reduction and fouling control

An Ding, Yingxue Zhao, Huu Hao Ngo, Langming Bai, Guibai Li, Heng Liang, Nanqi Ren, Jun Nan

《环境科学与工程前沿(英文)》 2020年 第14卷 第6期 doi: 10.1007/s11783-020-1275-4

摘要: Abstract • Effects of metabolic uncoupler TCS on the performances of GDMBR were evaluated. • Sludge EPS reduced and transformed into dissolved SMP when TCS was added. • Appropriate TCS increased the permeability and reduced cake layer fouling. • High dosage aggravated fouling due to compact cake layer with low bio-activity. The gravity-driven membrane bioreactor (MBR)system is promising for decentralized sewage treatment because of its low energy consumption and maintenance requirements. However, the growing sludge not only increases membrane fouling, but also augments operational complexities (sludge discharge). We added the metabolic uncoupler 3,3′,4′,5-tetrachlorosalicylanilide (TCS) to the system to deal with the mentioned issues. Based on the results, TCS addition effectively decreased sludge ATP and sludge yield (reduced by 50%). Extracellular polymeric substances (EPS; proteins and polysaccharides) decreased with the addition of TCS and were transformed into dissolved soluble microbial products (SMPs) in the bulk solution, leading to the break of sludge flocs into small fragments. Permeability was increased by more than two times, reaching 60–70 L/m2/h bar when 10–30 mg/L TCS were added, because of the reduced suspended sludge and the formation of a thin cake layer with low EPS levels. Resistance analyses confirmed that appropriate dosages of TCS primarily decreased the cake layer and hydraulically reversible resistances. Permeability decreased at high dosage (50 mg/L) due to the release of excess sludge fragments and SMP into the supernatant, with a thin but more compact fouling layer with low bioactivity developing on the membrane surface, causing higher cake layer and pore blocking resistances. Our study provides a fundamental understanding of how a metabolic uncoupler affects the sludge and bio-fouling layers at different dosages, with practical relevance for in situ sludge reduction and membrane fouling alleviation in MBR systems.

关键词: Gravity-driven membrane (GDM)     Energy uncoupling     Permeability     Sludge reduction     Membrane fouling     Fouling layer    

用以产生高纯度涡旋波束的宽带圆极化透射阵 Correspondence

邱靓婕1,2,3,4,李秀萍1,2,3,4,齐紫航1,2,3,4,赵文禹1,2,3,4,黄雨菡5

《信息与电子工程前沿(英文)》 2023年 第24卷 第6期   页码 927-934 doi: 10.1631/FITEE.2200539

摘要: 本文提出一款在Ka波段产生高纯度涡旋波束的宽带圆极化透射阵。为简化设计,所提出的透射单元由两个相同的组合构成,并用空气层将其隔开。亚波长结构以及双谐振特性确保了透射单元在28.4%的1-dB透射带宽内具有稳定的相移能力。基于此,加工测试了一款由喇叭天线馈电的方形口径透射阵。得益于蜂窝状布阵方式,所设计的透射阵可在28.5 GHz到38 GHz的宽带范围中辐射l=–1且模态纯度高于0.93的涡旋波束。测试的峰值增益为22.3 dBic,3-dB轴比带宽为27.6%。测试结果表明,本文提出的透射阵有潜力应用于高容量无线通信和高质量雷达成像方面。

关键词: 轨道角动量;涡旋波束;透射阵;宽带;高纯度    

空间衍射望远系统发展现状 Review Article

赵维1,3,4,王新1,刘华‡2,4,陆子凤2,4,卢振武5

《信息与电子工程前沿(英文)》 2020年 第21卷 第6期   页码 809-962 doi: 10.1631/FITEE.1900529

摘要: 基底微结构制作的薄膜衍射光学元件具备超轻质量(面密度小于0.1 kg/m2)和宽松表面形状公差(厘米级表面精度需求)两个重要特性,将其作为大口径望远镜的主镜可实现超大口径,超轻量化,同时降低发射成本。本文对国内外基于衍射光学的空间大口径望远系统的研究进展进行归纳和总结。首先阐述衍射望远系统的成像理论与组成结构,然后介绍衍射望远系统研究进展,最后总结衍射技术作为未来高分辨率空间侦查系统的发展趋势,提出我国应着重开展的相关工作。

关键词: 薄膜衍射光学元件;衍射望远系统;超大口径    

纹理分支网络:基于超声影像的慢性肾脏病筛查模型 Research Articles

郝鹏翼1,5,徐震宇1,田树元2,吴福理1,5,陈为3,5,吴健4,5,罗笑南6

《信息与电子工程前沿(英文)》 2020年 第21卷 第8期   页码 1119-1266 doi: 10.1631/FITEE.1900210

摘要: 慢性肾脏病是一种在世界范围内广泛存在的肾脏疾病。该疾病一旦发展到晚期,伴随而来的是严重并发症与较高死亡风险。因此,早期筛查对于慢性肾脏病诊治至关重要。超声作为一种无创方法,能动态观察肾脏形态和病理特征,常用于肾脏检查。本文提出一种新的卷积神经网络模型,称为纹理分支网络,基于超声影像作慢性肾脏病筛查。该模型通过在经典卷积神经网络中引入纹理分支来提取和优化纹理特征,可自动生成输入图像的纹理特征和深度特征,并使用融合信息进行分类。此外,通过迁移学习训练网络的主干部分,并在具有226张超声影像的数据集上开展实验。实验结果表明,该模型准确率和敏感度分别达到96.01%和99.44%,在慢性肾脏病筛查上具有一定有效性。

关键词: 慢性肾脏病;超声;纹理分支网络;迁移学习    

一种用于用户端设备且工作在2G/3G/4G/IMT/5G频段的小型化超宽带交叉振子天线 Correspondences

郭景丽1,崔伦1,刘英1,孙保华1,李肖锋2

《信息与电子工程前沿(英文)》 2022年 第23卷 第2期   页码 339-345 doi: 10.1631/FITEE.2000456

摘要: 设计了一种用于用户端设备(CPE)且工作在2G/3G/4G/IMT/5G频段的小型化超宽带交叉振子天线。此外,通过在交叉振子下方增加开缝的寄生贴片,天线整体的带宽能够扩展到5G sub-6 GHz频段。此外,对天线结构进行了加工和测试。

关键词: 5G;交叉振子;双极化天线;终端天线;超宽带    

Improvement in the synthesis of 2-(5-amino-1,2,4-thiadiazol-3-yl)-2-(Z)-methoxyiminoacetic acid 2-benzothiazolyl

GAO Shihao, SUN Chenghui, ZHAO Xinqi, GAO Changquan

《化学科学与工程前沿(英文)》 2008年 第2卷 第1期   页码 80-84 doi: 10.1007/s11705-008-0017-0

摘要: 2-(5-Amino-1,2,4-thiadiazol-3-yl)-2-(Z)-methoxyiminoacetic acid 2-benzothiazolyl thioester(III), an important intermediate of the fourth generation cephalosporins, was efficiently synthesized by reacting 2-(5-amino-1,2,4-thiadiazol-3-yl)-2-(Z)-methoxyiminoacetic acid (I) with 2,2′-dibenzothiazole disulfide (II) in the presence of triphenylphosphine. Effects of reaction time, temperature, solvents, catalysts and feeding molar ratio on the yield and quality of products were investigated, and an improved procedure suitable for industrial production was established. Using 1,2-dichloroethane as solvent, triphenylphosphine as reducer, and triethylamine as catalyst, (I) : (II) : (triphenylphosphine) = 1.0 : 1.0 : 1.0, the product was obtained at room temperature in 98.1% yield. The purity of the product without further purification is 98.7% determined by HPLC method. This procedure could be a suitable alternative to the traditional processes because of its easy handling, high yield and low cost.

关键词: 5-Amino-1     2     4-thiadiazol-3-yl     1     2-dichloroethane     important intermediate     2-benzothiazolyl thioester     temperature    

Effective regeneration of thermally deactivated commercial V-W-Ti catalysts

Xuesong SHANG, Jianrong LI, Xiaowei YU, Jinsheng CHEN, Chi HE

《化学科学与工程前沿(英文)》 2012年 第6卷 第1期   页码 38-46 doi: 10.1007/s11705-011-1167-z

摘要: An effective method for the regeneration of thermally deactivated commercial monolith SCR catalysts was investigated. Two types of regenerated solutions, namely NH Cl (1 mol/L) and dilute H SO (0.5 mol/L), were employed to treat the used catalyst. The effects of temperature and the regeneration process on the structural and textural properties of the catalysts were determined by X-ray diffraction, scanning electron microscopy, N adsorption/desorption, elemental analysis and Fourier transform infrared spectroscopy. The results suggest that the anatase phase of the used catalyst is maintained after exposure to high temperatures. Some of the catalytic activity was restored after regeneration. The catalyst regenerated by aqueous NH Cl had a higher activity than that of the catalyst treated by dilute H SO . The main reason is that the NH generated from the decomposition of NH Cl at high temperatures can be adsorbed onto the catalyst which promotes the reaction. The aggregated V O were partially re-dispersed during the regeneration process, and the intrinsic oxidation of ammonia with high concentrations of O is a factor that suppresses the catalytic activity.

关键词: V2O5-WO3/TiO2 catalysts     thermal deactivation     regeneration     NH4Cl     dilute H2SO4 solution    

标题 作者 时间 类型 操作

Design, synthesis and HIV-RT inhibitory activity of novel thiazolidin-4-one derivatives

Hua CHEN, Zaihong GUO, Qingmei YIN, Xiaoxu DUAN, Yunjing GU, Xiaoliu LI

期刊论文

Microwave-assisted synthesis and antimicrobial activities of 2-aryl-3-(naphthalene-1 or 2-yl)-1,3-thiazolidin-4-ones

Hua CHEN, Yanan LI, Jie BAI, Lian ZHAO, Xiangguo YUAN, Xiaoliu LI, Keqiang CAO

期刊论文

Dechlorination of 2,2′,4,4′,5,5′-hexachlorobiphenyl by thermal reaction with activated carbon-supported

Yifei SUN, Xin FU, Wei QIAO, Wei WANG, Tianle ZHU, Xinghua LI

期刊论文

5′-tiRNA-Gln inhibits hepatocellular carcinoma progression by repressing translation through the interactionwith eukaryotic initiation factor 4A-I

期刊论文

On the monolayer dispersion behavior of Co3O4 on HZSM-5 support: designing applicable

期刊论文

Facile controlled synthesis of hierarchically structured mesoporous Li4Ti5O12/C/rGO composites as high-performance

Cehuang FU, Shuiyun SHEN, Ruofei WU, Xiaohui YAN, Guofeng XIA, Junliang ZHANG

期刊论文

UI图层合并器:基于计算机视觉与边界先验的UI图层合并方法

陈云农1,5,甄焱鲲4,施楚宁2,李佳智2,陈柳青2,3,5,李泽健1,3,5,孙凌云2,3,5,周婷婷4,常艳芳4

期刊论文

新闻媒体眼中的中国:新冠肺炎疫情下的案例研究

黄宏1,2,3,4,陈哲学1,2,3,4,石宣化1,2,3,4,王晨旭1,2,3,4,何泽鹏1,2,3,4,金海1,2,3,4,张明新5,李宗亚5

期刊论文

Metabolic uncoupler, 3,3′,4′,5-tetrachlorosalicylanilide addition for sludge reduction and fouling control

An Ding, Yingxue Zhao, Huu Hao Ngo, Langming Bai, Guibai Li, Heng Liang, Nanqi Ren, Jun Nan

期刊论文

用以产生高纯度涡旋波束的宽带圆极化透射阵

邱靓婕1,2,3,4,李秀萍1,2,3,4,齐紫航1,2,3,4,赵文禹1,2,3,4,黄雨菡5

期刊论文

空间衍射望远系统发展现状

赵维1,3,4,王新1,刘华‡2,4,陆子凤2,4,卢振武5

期刊论文

纹理分支网络:基于超声影像的慢性肾脏病筛查模型

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