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21.
Hongbing Song Lei Liu Bingxiao Feng Haozhong Wang Meng Xiao Hengjun Gai Yubao Tang Xiaofei Qu Tingting Huang 《中国化学工程学报》2021,40(12):293-303
In this work, modified g-C3N4 was fabricated successfully by calcination of ionic liquid (IL) and urea. The addition of IL changed the polymerization mode of urea, induced the self-assembly of urea molecules, modified the morphological structure of the tightly packed g-C3N4, and extended the electron conjugation system. When using 1-butyl-3-methylimidazolium chloride ([Bmim]Cl) as a modifier, the heteroatom Cl could be inserted into the g-C3N4 to optimize the electronic structure. The results of characterizations indicate that the unique structure of modified g-C3N4 has an expanded electron delocalization range, introduces an interlayer charge transmission channel, promotes the charge transmission, reduces the band gap, enhances the absorption of visible light, and inhibits electron-hole recombination. Modified g-C3N4 showed excellent photocatalytic performance for the degradation of rhodamine B and tetracycline. Furthermore, the effect of different anions in 1-butyl-3-methylimidazolium salts ([Bmim]Cl, [Bmim]Br, [Bmim][BF4], and [Bmim][PF6]) on the structure and function of g-C3N4 are discussed. 相似文献
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Ann-Kathrin Eichelmann George C. Mayne Karen Chiam Steven L. Due Isabell Bastian Frederike Butz Tingting Wang Pamela J. Sykes Nicholas J. Clemons David S. Liu Michael Z. Michael Christos S. Karapetis Richard Hummel David I. Watson Damian J. Hussey 《International journal of molecular sciences》2021,22(11)
TP53 gene mutations occur in 70% of oesophageal adenocarcinomas (OACs). Given the central role of p53 in controlling cellular response to therapy we investigated the role of mutant (mut-) p53 and SLC7A11 in a CRISPR-mediated JH-EsoAd1 TP53 knockout model. Response to 2 Gy irradiation, cisplatin, 5-FU, 4-hydroxytamoxifen, and endoxifen was assessed, followed by a TaqMan OpenArray qPCR screening for differences in miRNA expression. Knockout of mut-p53 resulted in increased chemo- and radioresistance (2 Gy survival fraction: 38% vs. 56%, p < 0.0001) and in altered miRNA expression levels. Target mRNA pathways analyses indicated several potential mechanisms of treatment resistance. SLC7A11 knockdown restored radiosensitivity (2 Gy SF: 46% vs. 73%; p = 0.0239), possibly via enhanced sensitivity to oxidative stress. Pathway analysis of the mRNA targets of differentially expressed miRNAs indicated potential involvement in several pathways associated with apoptosis, ribosomes, and p53 signaling pathways. The data suggest that mut-p53 in JH-EsoAd1, despite being classified as non-functional, has some function related to radio- and chemoresistance. The results also highlight the important role of SLC7A11 in cancer metabolism and redox balance and the influence of p53 on these processes. Inhibition of the SLC7A11-glutathione axis may represent a promising approach to overcome resistance associated with mut-p53. 相似文献
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A series of pH‐sensitive and thermosensitive polymer networks were first obtained by copolymerization of telechelic poly(1,3‐dioxolane) (PDXL) with acrylic acid (AA), acrylamide (AM), and N‐isopropylacrylamide (NIPAM), respectively. The copolymerization of PDXL diacrylate (PDXLDA) with AA, AM, or NIPAM is expected to lead to polymer networks in which homopolymeric segments of the monomer are connected by polyacetal segments. As a combination of these two parts, these polymer networks can have some interesting physical properties. For example, the copolymer networks of poly(AA‐b‐DXL) showed pH sensitivity, and both the copolymer networks of poly(AM‐b‐DXL) and poly(NIPAM‐b‐DXL) showed temperature sensitivity. Moreover, because of the low ceiling temperature of polyDXL, the networks containing polyacetal segments (PDXL) can degrade by treatment with a trace of appropriate cationic initiator. The polymer networks prepared were characterized by Fourier transform infrared, differential scanning calorimetry, and swelling data. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 3002–3006, 2002; DOI 10.1002/app.2329 相似文献
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本文提出一种复合各向异性扩散滤波算法,将降斑各向异性扩散(Speckle reducing anisotropic diffusion,SRAD)模型中对边缘敏感的瞬态系数(Instantaneuos coefficient of variation,ICOV)算子运用到了非线性相干扩散(Nonlinear coherent diffusion,NCD)相干模型中,并基于统计学提出ICOV算子的相关系数矩阵对图像的相关度进行度量,系数矩阵的值是每个ICOV算子与其所在行与列的相关度,此相关度的值在边缘附近会取到极大值,这个对图像的边缘检测有很好的度量,根据每个像素与其周围像素的相关度对边缘附近的扩散的强度进行修改,对图像进行更为之有效、更准确的非线性去噪与边缘加强.实验结果表明,与其他各向异性算法相比,本算法可获得更好的性能指标,具有更好的去噪效果和保留边缘功能. 相似文献
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Soap‐free emulsion copolymerization of perfluoroalkyl acrylate (FA)/methyl methacrylate (MMA)/n‐butyl acrylate (n‐BA) was carried out in the presence of sodium 2‐acrylamide‐2‐methyl propanesulfonate (AMPSNa) as a reactive surfactant and potassium persulfate (KPS) as an initiator. An analysis of the effects of concentration of AMPSNa, KPS, FA as well as polymerization temperature on the kinetic features (rate of polymerization) and colloidal characteristics (mean particle diameter, particle disperse index, particle numbers, and surface charge density) was followed. NMR, FTIR, AFM, and fluorine‐selective electrode analysis were used to characterize the composition and morphology of the FA copolymers. Both AFM analysis and contact angle measurements strongly implied that the fluorinated segments migrated to the outmost surface and created films with lower surface energy. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 2438–2444, 2007 相似文献
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针对催化剂TiO_2禁带宽度较宽、光响应范围较窄的问题,对TiO_2进行改性,采用溶胶凝胶法制备了不同复合比例的WO_3/TiO_2催化剂以提高TiO_2的光催化活性。应用SEM,BET,XRD,UV-Vis,FT-IR等方法对催化剂进行表征,分析了不同复合比对WO_3/TiO_2样品形貌、晶型、比表面积和产氢速率的影响。当入射波长为300~600 nm,2%WO_3/TiO_2的吸光度大于TiO_2的吸光度,吸收带边红移。通过300 W氙灯照射进行光解水制氢的测试,评价了不同WO_3/TiO_2样品的光催化分解水产氢活性。结果表明:复合比为2%时,WO_3/TiO_2的光解水产氢活性最佳,最高可达14 445.3μmol/(h·g),其产氢速率是TiO_2的10倍,同时探讨分析了光催化反应机理。这将在太阳能光解水产氢领域有着广泛的应用前景。 相似文献
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邵婷婷 《单片机与嵌入式系统应用》2014,(7):35-37
设计了一款具有倾斜补偿功能的三轴磁阻电子罗盘,并对样机系统做了误差补偿。本系统以磁阻传感器HMC1043和MEMS加速度传感器ADXL203为信号采集模块,以MSP430F149单片机为信号处理模块,分别获取、处理磁场和重力加速度信息,并通过液晶显示模块LCM6432ZK显示载体的航向角和姿态角。结合经典的椭圆假设法和傅里叶级数模型,对系统的误差进行补偿。实验结果表明,设计的磁阻电子罗盘实现了集成化和智能化,能实时显示载体的航向角和姿态角,航向误差可稳定在±0.6°以内。 相似文献