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81.
利用哌嗪与自制的聚醚/环氧硅油中间体反应合成了一种哌嗪改性聚醚基聚二甲基硅氧烷PPEPS,对其进行了结构表征和应用。结果表明:原料含氢硅油的平均相对分子质量、PPEPS的硅含量对其应用性能有影响。增加原料含氢硅油的平均相对分子质量,提高硅含量,可改善PPEPS的柔软性,而对织物的吸湿性影响不大。  相似文献   
82.
The polymeric metal complexes of CoII, NiII, CuII, ZnII, CdII , CeIII, LaIII and UO2 II with 1,4-[5-disulphonyl-8-hydroxyquinoline]piperazine have been synthesized. It has been found that the ligand coordinates to the metal ion as a bibasic tetradentate chelating agent and can form polymeric metal complexes. The structure of the isolated metal complexes is supported by chemical analysis, thermoanalytical data, and conductivity measurements, as well as uv-visible, 1H-NMR, and IR spectroscopy. The stoichiometry of these metal complexes is M:L=2:3. A tetrahedral stereochemical configuration is suggested for the polymeric metal complexes with the exception of the CeIII and LaIII complexes, which form six-coordinate polymeric metal complexes.  相似文献   
83.
张瑞明  张洁  刘荣杰  田忠 《化学工程》2007,35(11):25-28
在确定气固相合成无水哌嗪的最佳工艺条件、筛选出最佳催化剂活性组分、确定催化剂制备的最佳工艺条件后,为了进一步研究中试放大,需对在确定工艺条件及所采用催化剂的结构和粒径的条件下催化合成无水哌嗪的宏观动力学进行研究。实验采用改性后的ZSM-5分子筛Φ2 mm×2 mm柱状催化剂,以工业品乙二胺(EDA)为原料,选用平推流反应器,气固相催化法合成无水哌嗪和副产物三乙烯二胺。在350—370℃下,建立了合成无水哌嗪和三乙烯二胺的宏观动力学模型。此模型的建立可以指导中试放大和工业化生产。  相似文献   
84.
Nanofiltration (NF) membranes were fabricated by using piperazine (PIP) and trimesoyl chloride (TMC) by conventional and spray-applied interfacial polymerization methods, studying the effect of the application method for both phases, the number of applied layers, and the displacement speed for the spray application. A polysulfone ultrafiltration membrane was used as support. NF membranes were characterized by different spectroscopic, microscopic, and physicochemical techniques. Rejection capacity was evaluated for sodium chloride (NaCl), sodium sulfate (Na2SO4), and magnesium sulfate (MgSO4) salts; the decreasing rejection order was Na2SO4 > MgSO4 > NaCl for each NF membrane. NF membrane prepared with one layer of the sprayed out TMC solution and conventional application of PIP solution exhibited the highest salt rejection (99% for 1000 ppm Na2SO4) and a permeated flux of 10.28 L m−2 h−1 at 0.55 MPa. The modified method is a facile-reproducible preparation methodology that reduces the consumption of time, effort, and reagents leading to a scalable manufacturing process for separation technology. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 48129.  相似文献   
85.
Molecular hybridization approach is a promising structural modification tool to design new chemical entities (NCEs) by mimicking two different pharmacophoric units into one scaffold to enhance the biological properties. With this aim, combretastatin-A4 acids were integrated with sulfonyl piperazine scaffolds as a one molecular platform and evaluated for their in vitro antiproliferative activity against a panel of human cancer lines cell lines namely, lung (A549), mouse melanoma (B16F10), breast (MDA MB-231and MCF-7) and colon (HCT-15) by MTT assay. Amongst which the compound (E)-3-(4-Chlorophenyl)-1-(4-((4-chlorophenyl)sulfonyl)piperazin-1-yl)-2-(3,4,5-trimethoxyphenyl)prop-2-en-1-one ( 5 ab ) displayed significant IC50 values in the range of 0.36 to 7.08 μm against the selected cancer cell lines. Moreover, 5 ab was found to be the most potent member of this series with IC50 0.36±0.02 μm . Further investigations revealed that the compound 5 ab displayed significant inhibition of tubulin assembly with IC50 5.24±0.06 μm and molecular docking studies also disclosed the binding of 5 ab effectively in CA4 binding space at the colchicine binding site. The flow cytometric analysis demonstrated that the compound 5 ab caused cell cycle arrest at G2/M phase in A549 cells. Compound 5 ab induced apoptosis in A549 cells which was further evaluated by different staining assays such as DAPI and AO which undoubtedly speculated, the induction of apoptosis. To study the anti-migration with 5 ab , cell migration/scratch wound assay was performed and the extent of apoptosis was studied by Annexin-V, including mitochondrial potential by JC-1 staining.  相似文献   
86.
简述了6种常见的1-[2-(2-羟基乙氧基)乙基]哌嗪的合成路线,并对其优缺点进行了比较。  相似文献   
87.
A simple, practical, and metal‐free protocol has been developed for the synthesis of sulfonamides from sodium sulfinates and various amines through an iodine‐mediated S N bond formation reaction at room temperature. This green reaction is cost‐effective, operationally straightforward, and especially proceeds under very mild conditions to afford the target products in good to excellent yields (up to 98%).

  相似文献   

88.
The piperazine pyrophosphate (PPAP) combined with aluminum diethylphosphinate (AlPi) with a certain mass fraction and then incorporated into thermoplastic elastomer (TPE) composites composed of oil extended styrene–ethylene–butadiene–styrene block copolymer and polypropylene. The fire retardancy, thermal behavior, mechanical performance, and flame retardant mechanism of TPE materials were investigated in detail. The results demonstrated that 1.6 mm TPE composites reached UL-94 V-0 grade during vertical burning tests and the limiting oxygen index value was 28.5% when 25 wt % PPAP/AlPi with the mass ratio of 4:1 was incorporated. The introduction of PPAP/AlPi improved the residual mass and thermal stability, and stimulated to produce the char layer with high quality. The formed char layer exerted shielding effect and AlPi could inhibit the flame in gas phase. Consequently, the PPAP/AlPi system evoked fire retardant effects in condensed and gas phase simultaneously, and the fire resistance of the TPE composites was enhanced. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 47711.  相似文献   
89.
哌嗪紫外吸收弱,最强峰对应波长处吸光度线性范围窄,因此紫外分光光度法在呱嗪检测中的应用受到了限制。根据哌嗪紫外吸收特点.探讨了对哌嗪水溶液进行紫外分光光波法快速测定的方法.该方法不采用哌嗪紫外吸收最强蜂对应波长作为测定波长,而采用了基线干噪和波段积分等手段对哌嗪紫外吸收光潜进行了数据处理,因此该方法的准确度和精确度得到了保证,回收率实验和精密度实验的结果表明.该方法的准确和精确度良好.  相似文献   
90.
为了研究新型哌嗪衍生物的可生物降解性和摩擦学性能,设计合成了环保型润滑油添加剂1,4-双(二硫代甲酸乙酰乙胺)哌嗪(DAP)。采用元素分析和红外光谱进行结构表征,考察了其热稳定性能、可生物降解性和在液体石蜡油(LP)中的极压抗磨性能,利用扫描电子显微镜(SEM)和X射线光电子能谱仪(XPS)分析了钢球的磨损表面形态。结果表明:合成的化合物热稳定性能好并具有良好的可生物降解性;化合物添加到LP中后具有很好的极压抗磨性能,并在摩擦过程中发生了化学吸附及摩擦化学反应,在摩擦区域金属表面上形成了一层复杂边界润滑膜,从而起到了良好的抗磨减摩的作用。  相似文献   
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