Determination of metastable region for sodium acetate

溶液的介稳区是结晶的基础研究之一.利用静态法测定醋酸钠在水中不同温度下的溶解度,同时利用激光散射法测定醋酸钠在不同温度、搅拌速率、降温速率条件下的超溶解度,得到溶解度与超溶解度的曲线从而拟合出醋酸钠在水中溶解度和超溶解度的方程,确定介稳区范围.研究结果表明,醋酸钠的溶解度随着温度的升高而升高.在一定条件下,搅拌速率越大、温度越高、降温速率越快,介稳区宽度越窄.     

阳离子荧光染料的合成及其性能研究

合成了一种新型双阳离子型荧光染料—反,反-1,4-双{2-[4-(N-乙基)溴化吡啶基]乙烯基}苯(DPPB),采用红外光谱和核磁共振谱仪对其进行了结构表征,通过染色实验研究其在腈纶织物上的染色性能及色牢度,同时研究了其单光子荧光性能。结果表明,DPPB的荧光性能良好,在腈纶织物上有良好的染色性能,所染织物具有蓝绿色荧光效果。     

信息技术在化纤行业中的应用

从化纤行业特点、物资采购特点及物资管理作用3方面,分析信息技术在化纤行业中的重要性,引出ERP是企业信息化的主体应用,并围绕ERP物资管理模块构成和功能,以中国石化仪征化纤股份有限公司(以下简称"仪征化纤")为例,简要阐述信息技术给化纤行业带来的经济效益。     

A novel optical aerosol detector utilizing an optic fiber with conductive polymer coating

The detection of atmospheric aerosol particles is becoming an important issue in many fields such as environmental science, occupational medicine, semiconductor industry and material science. In the present paper, we utilized the conductive polymer, polypyrrole (PPy), as a sensitive membrane for detecting aerosol particles optically. A polymer optical fiber reflectance probe is constructed by depositing the PPy nanofilm at the end face of the fiber. The sensor principle relies on the change in the refractive index of the PPy nanofilm upon its interaction with aerosol nanoparticles and on the electrostatic induction between aerosol particles and the PPy nanofilm, which leads to a change in the reflected intensity. For preliminary evaluation of optical aerosol detector, three types of aerosol particles, NaCl, black carbon (BC) and polystyrene latex (PSL), are selected. The fabricated fiber optic reflectance probe using the PPy nanofilm shows distinct variations in the reflected light intensity depending on the type of aerosol particle and its properties. The proposed sensing approach may promote the use of conductive polymers in optical techniques for the detection of atmospheric aerosols.     

Stretching-induced interfacial crystalline structures and relevant mechanical properties in melt-spun polypropylene/whisker composite fibers

Crystalline structures especially the interfacial crystalline layers of semi-crystalline polymer/filler composites are markedly affected by the extensional force and keep an important role in macroscopic properties. In this study, we prepared the polypropylene and SiO₂–MgO–CaO whisker (SMCW) composite fibers by melt-spun technology. The structure–property relationship of the PP/SMCW composite fibers was investigated by scanning electron microscopy, polarizing light microscopy, differential scanning calorimeter, the polarized Fourier transform infrared spectroscopy and tensile test. Two different interfacial crystalline structures were observed by adopting two drawn ratios – shish-calabash structure obtained at the low drawn ratio and transcrystalline (TC) structure obtained at the high drawn ratio. Remarkable reinforcement of the fibers was realized for the composite fibers prepared at high drawn ratio, compared with that obtained at the low drawn ratio. It was deduced that the formation of transcrystalline structure could result in a better interfacial interaction than shish-calabash structure, and could be one of the most important reasons for the large improvement of tensile properties of composite fibers fabricated at high drawn ratio.     

New tetraphenylethylene-containing conjugated polymers: Facile synthesis,aggregation-induced emission enhanced characteristics and application as explosive chemsensors and PLEDs

In this paper, tetraphenylethylene (TPE) units, one of the typical aggregation-induced emission (AIE) moieties, are utilized to construct a new functional polyfluorene (PF) P1, which exhibited the exciting property of the aggregation-induced emission enhancement (AIEE), instead of the aggregation-caused quenching (ACQ) of normal PFs, and could probe the explosive with high sensitivity both in the nanoparticles and solid state. Three other TPE-containing polymers, P2–P4, were also successfully prepared, and demonstrated good performance as explosive chemosensors and light-emitting materials. P3, bearing carbazole as hole-transporting units showed the best performance with a maximum luminance efficiency of 1.17 cd/A and a maximum brightness of 3609 cd/m² at 12.9 V in its light-emitting diode device.     

Direct synthesis of self-aligned single-walled carbon nanotubes on paper

A technique of micro chemical vapor deposition (μCVD) is reported for the direct synthesis of self-aligned SWCNTs on various substrates including plastics and paper. With the guidance of micro flow channels, self-aligned SWCNTs up to hundreds of microns in length have been collected. Both Raman spectral and transmission electron microscopy have validated the high quality of these SWCNTs. In conclusion, μCVD could be a versatile method to synthesize pristine SWCNTs for various applications.     

Platinum supported on reduced graphene oxide as a catalyst for hydrogenation of nitroarenes

Reduced graphene oxide (RGO)-supported platinum (Pt) catalyst was prepared by simple ethylene glycol (EG) reduction and used for hydrogenation of nitroarenes. Characterizations showed that EG as a reductant exhibited more advantages than the widely used hydrazine hydrate to fabricate monodispersed, small sized Pt nanoparticles on the surface of RGO. The yield of aniline over the Pt/RGO-_EG catalyst reached 70.2 mol-_AN/(mol-_Pt min) at 0 ^oC, which is 12.5 and 19.5 times higher than that of multi-walled carbon nanotube- and active carbon-supported Pt catalysts, respectively. When the reaction temperature was increased to 20 ^oC, the catalytic activity of Pt/RGO-_EG jumped to 1138.3 mol-_AN/(mol-_Pt min), and it was also extremely active for the hydrogenation of a series of nitroarenes. The unique catalytic activity of Pt/RGO-_EG is not only related to the well dispersed Pt clusters on the RGO sheets but also the well dispersion of Pt/RGO-_EG in the reaction mixture.     

白藜芦醇磺酸酯的合成及抗氧化、抗肿瘤活性的研究

以白藜芦醇和2, 4-二硝基苯磺酰氯为原料,通过酯化法得到白藜芦醇磺酸酯,通过NMR和LC-MS确定了该化合物结构。以维生素C为阳性对照,研究白藜芦醇磺酸酯对2, 2-联苯基-1-苦基肼(DPPH)自由基和2, 2′-联氮-双-3-乙基苯并噻唑啉-6-磺酸(ABTS)自由基的清除活性和抗氧化活性;噻唑蓝(MTT)法研究其对人肺癌细胞A549的增殖活性。实验结果表明,目标产物收率为33.1%。同时,目标产物在浓度为1.0 mg/mL时,对DPPH自由基和ABTS自由基的清除率分别为31.6%和42.7%,抗氧化活性均高于白藜芦醇,但低于维生素C;目标产物对人肺癌细胞A549具有较好抑制作用,IC50值为(10.2±0.37)μg/mL。     

白藜芦醇丙烯酸酯的合成及抗氧化活性研究

以白藜芦醇为先导化合物,合成了白藜芦醇丙烯酸酯,以获得具有更好抗氧化活性的白藜芦醇衍生物。以白藜芦醇和丙烯酰氯为原料,酯化法得到白藜芦醇丙烯酸酯。以维生素C为阳性对照,研究白藜芦醇丙烯酸酯对2,2-联苯-1-苯基肼(DPPH)自由基的清除活性和抗氧化活性。用NMR和HRLC-MS对白藜芦醇丙烯酸酯进行了表征。目标产物白藜芦醇丙烯酸酯收率为30.2%。白藜芦醇丙烯酸酯的抗氧化活性高于白藜芦醇,但低于维生素C。合成得到了白藜芦醇丙烯酸酯,其反应路线简单易行,条件温和,产物抗氧化活性较先导化合物有所提高。