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991.
采用环状反应器模拟原水输水管道, 考察氯胺(NH2Cl)及其与二氧化氯联用(NH2Cl/ClO2)对溶解性有机物(DOM)、溶解性有机碳(DOC)和UV254降解以及有机物荧光特性的影响。结果表明:NH2Cl或NH2Cl/ClO2对DOC、UV254和DOM的降解均产生较大的影响。相比NH2Cl, NH2Cl/ClO2的影响更大, 但是有机物降解的恢复速度没有明显差异, DOC、UV254和DOM的降解分别在停止投加氧化剂的第5 d、4 d和1 d恢复。投加氧化剂后, 芳香族有机物以向易生物降解的极性有机物的转化为主, 溶解性有机物的可生物降解能力增加。NH2Cl和NH2Cl/ClO2作用后, 类蛋白质物质以及紫外区类腐殖质类物质明显减少。NH2Cl/ClO2更易破坏有机物中的芳香族化合物的结构, 而NH2Cl氧化使得有机物分子结构中羰基、羟基、羧基和胺基等官能团增加, 从而有机物可生物降解能力较强。NH2Cl和NH2Cl/ClO2作用后, 有机物降解作用可恢复至比未加氧化剂更高的水平, 基于卤代副产物生成的考虑, 相比NH2Cl, NH2Cl/ClO2更适合用于原水输水管道的氧化。 相似文献
992.
993.
The mechanical properties of poly(1‐butene) reinforced by pristine multiwalled carbon nanotubes (MWNTs) and polypropylene‐grafted MWNTs (PP‐g‐MWNTs) were evaluated. The incorporation of pristine MWNTs to PB led to an improvement in stiffness, but not in strength, ductility, and toughness. In comparison, PP‐g‐MWNTs were able to improve the stiffness, strength, and toughness of PB significantly, without compromising the ductility. The mechanical properties of PB improved with increasing amount of PP‐g‐MWNTs up to an effective MWNT content of 1.5 wt%. Further increase in the effective MWNT content led to a downturn in mechanical properties due to the existence of MWNTs bundles as observed by microscopy. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献
994.
Na-Na Wang Zhi-Heng Li He Zhao Yan-Fang Tao Li-Xiao Xu Jun Lu Lan Cao Xiao-Juan Du Li-Chao Sun Wen-Li Zhao Pei-Fang Xiao Fang Fang Guang-Hao Su Yan-Hong Li Gang Li Yi-Ping Li Yun-Yun Xu Hui-Ting Zhou Yi Wu Mei-Fang Jin Lin Liu Jian Ni Jian Wang Shao-Yan Hu Xue-Ming Zhu Xing Feng Jian Pan 《International journal of molecular sciences》2015,16(1):1266-1292
Polo-like kinase 1 (PLK1) is highly expressed in many cancers and therefore a biomarker of transformation and potential target for the development of cancer-specific small molecule drugs. RO3280 was recently identified as a novel PLK1 inhibitor; however its therapeutic effects in leukemia treatment are still unknown. We found that the PLK1 protein was highly expressed in leukemia cell lines as well as 73.3% (11/15) of pediatric acute myeloid leukemia (AML) samples. PLK1 mRNA expression was significantly higher in AML samples compared with control samples (82.95 ± 110.28 vs. 6.36 ± 6.35; p < 0.001). Kaplan-Meier survival analysis revealed that shorter survival time correlated with high tumor PLK1 expression (p = 0.002). The 50% inhibitory concentration (IC50) of RO3280 for acute leukemia cells was between 74 and 797 nM. The IC50 of RO3280 in primary acute lymphocytic leukemia (ALL) and AML cells was between 35.49 and 110.76 nM and 52.80 and 147.50 nM, respectively. RO3280 induced apoptosis and cell cycle disorder in leukemia cells. RO3280 treatment regulated several apoptosis-associated genes. The regulation of DCC, CDKN1A, BTK, and SOCS2 was verified by western blot. These results provide insights into the potential use of RO3280 for AML therapy; however, the underlying mechanisms remain to be determined. 相似文献
995.
以二聚脂肪酸、二乙烯三胺、尿素等为原料制备室温自修复型聚酰胺。通过溶液水热法制备导电单质钴颗粒,并采用纳米复合工艺将导电单质钴颗粒掺杂入自修复聚酰胺体系中,经高温模压制得一种新型钴基自修复聚酰胺导电高分子材料。采用傅里叶变换红外光谱仪、X射线衍射仪、扫描电子显微镜等仪器对单质钴和自修复聚酰胺进行结构表征。系统研究了自修复聚酰胺的自修复能力及抗溶胀性能,以及自修复导电高分子材料的导电和自修复性能。结果表明,所制备的单质钴平均粒径为3.43μm,且表面粗糙易于与聚酰胺基体复合;自修复聚酰胺基体在室温下的自修复次数可达20余次;当交联剂尿素用量为6.6 g/20 g二聚脂肪酸或交联温度为145℃时,自修复聚酰胺对水、碱溶液和油具有较好的综合抗溶胀性能。当单质钴质量分数达到50%后,自修复导电高分子材料的导电率发生突变,导电能力大幅提升;单质钴的加入降低了材料的自修复能力,但单质钴质量分数为50%的材料在室温下的自修复次数仍可达10余次。由于这种材料同时具有较好的导电性能和自修复性能,有望应用于可穿戴装备、电子器件等领域。 相似文献
996.
Chutian Xing Tiefeng Wang Kunyu Guo Jinfu Wang 《American Institute of Chemical Engineers》2015,61(4):1391-1403
Pressure has a significant effect on bubble breakup, and bubbles and droplets have very different breakup behaviors. This work aimed to propose a unified breakup model for both bubbles and droplets including the effect of pressure. A mechanism analysis was made on the internal flow through the bubble/droplet neck in the breakup process, and a mathematical model was obtained based on the Young–Laplace and Bernoulli equations. The internal flow behavior strongly depended on the pressure or gas density, and based on this mechanism, a unified breakup model was proposed for both bubbles and droplets. For the first time, this unified breakup model gave good predictions of both the effect of pressure or gas density on the bubble breakup rate and the different daughter size distributions of bubbles and droplets. The effect of the mother bubble/droplet diameter, turbulent energy dissipation rate and surface tension on the breakup rate, and daughter bubble/droplet size distribution was discussed. This bubble breakup model can be further used in a population balance model (PBM) to study the effect of pressure on the bubble size distribution and in a computational fluid dynamics‐population balance model (CFD‐PBM) coupled model to study the hydrodynamic behaviors of a bubble column at elevated pressures. © 2014 American Institute of Chemical Engineers AIChE J, 61: 1391–1403, 2015 相似文献
997.
An Amphiphilic BODIPY‐Porphyrin Conjugate: Intense Two‐Photon Absorption and Rapid Cellular Uptake for Two‐Photon‐Induced Imaging and Photodynamic Therapy
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Dr. Tao Zhang Dr. Rongfeng Lan Longlong Gong Dr. Baoyan Wu Yuzhi Wang Dr. Daniel W. J. Kwong Prof. Wai‐Kwok Wong Dr. Ka‐Leung Wong Prof. Da Xing 《Chembiochem : a European journal of chemical biology》2015,16(16):2357-2364
The new amphiphilic BODPY‐porphyrin conjugate BZnPP and its precursor BZnPH were synthesised, and their linear and two‐photon photophysical properties, together with their cellular uptake and photo‐cytotoxicity, were studied. This amphiphilic conjugate consists of a hydrophobic BODIPY moiety and a hydrophilic tetra(ethylene glycol) chain bridging a cationic triphenylphosphonium group to an amphiphilic porphyrin ZnP through acetylide linkers at its meso positions. A large two‐photon absorption cross‐section (σ=1725 GM) and a high singlet oxygen quantum yield (0.52) were recorded. Intense linear‐ and two‐photon‐induced red emissions were also observed for both BZnPP and BZnPH. Further in vitro studies showed that BZnPP exhibited very efficient cellular uptake and strong photocytotoxic but weak dark cytotoxic properties towards human breast carcinoma MCF‐7 cells. In summary, the two‐photon‐induced emission and the potent photo‐cytotoxicity of BZnPP make it an efficacious dual‐purpose tumour‐imaging and photodynamic therapeutic agent in the tissue‐transparent spectral windows. 相似文献
998.
999.
邢瑞芝 《化学反应工程与工艺》1996,12(4):424-428
从环氧乙烯的易燃易爆性着手,剖析了传统式非离子表面活怀剂的生产中的不安全性,介绍了一种新型的安全性反应器。 相似文献
1000.