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101.
由于我国染料及中间体行业近三十年来发展迅猛,而染料企业大多数是小型厂,染料品种繁多,在化工系统中,这一行业目前几乎是污染最严重、污染面最大、治理最差的。同时,一些发达国家把污染重、难治理的产品关停,转向发展中国家生产,染料中间体便是其中之一。所以我国大量的小型乡镇企业治理难度就更大了。不同染料生产原料、工艺过程不同,所排“三废”即有共同的特性,又有各自特点,因此需要针对各自的不同分别处理。本文从废气、有机废液和废渣、废水三方面详细叙述了工业上常用的治理方法及适用条件。并例举了几类排放量较大的废水的治理方法。  相似文献   
102.
The study on the dynamic viscoelastic properties of grafted carbon black (g‐CB) filled low‐density polyethylene (LDPE) was carried out. Because of formation of CB networking, the characteristic modulus plateau and loss tangent arc appears. Addition of grafting monomer like butyl acrylate (BA) and acroleic acid (AA) enhances the interaction between particles and matrix due to accelerated formation of micronetworking in the composites induced by forming branch chains of AA and BA with multiunit. The decrease of the temperature corresponding to αc mechanical relaxation together with AA (BA) addition given by the position of loss tangent (tan δ) peak for LDPE is owed to the formation of long‐chain polymer grafted between CB and the matrix, which facilitates the slip of the lamella of LDPE. The influence of maleic anhydride (MA) on enhancing interaction between LDPE and CB is not so pronounced, as compared with AA and BA because of no formation of long chain between CB particle and polymer matrix. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 4127–4132, 2006  相似文献   
103.
Titanium dioxide (TiO2) nanotube arrays were prepared by electrochemical anodization of titanium sheets in the glycerol 176 mL/H2O 44 mL/NH4F 0.5 wt% electrolytes modified with H2SO4 and NaAc addition. The surface morphologies, average inner diameter, and the length of the nanotube arrays changed with the solution pH in the range from 5.6 to 4.0 by adding H2SO4. A uniform surface morphology of the nanotubes with average inner diameter of ∼80 nm and a length of ∼1000 nm was obtained when the solution pH was 5.0. The growth rates of the nanotubes were remarkably enhanced by NaAc addition in the range of 0.04–0.14 M . With NaAc addition of 0.10 M , the length of the nanotube arrays reached 4.16 μm after an 8-h anodization, increasing 3.23 μm compared with no NaAc addition. The relationship between solution pH and growth of TiO2 nanotubes was analyzed by current–time curves, solution electrical conductivities, and scanning electron microscopy (SEM), and the role of NaAc was also discussed based on SEM and solution electrical conductivities.  相似文献   
104.
随着SG186系统建设不断向企业的覆盖与延伸,信息网络的强健与否成为制约信息化系统应用的重要因素。本文通过对网络冗余技术的介绍,结合公司信息网络结构实际情况,通过应用实例分析,阐述如何合理使用网络冗余技术,确保信息网络的高可靠性。  相似文献   
105.
Two new poly(p‐phenylenevinylene) (PPV) derivatives containing oxadiazole moiety (OXA‐PPV1 and OXA‐PPV2) were synthesized by the Wittig condensation polymerization reaction. Their thermal and light‐emitting properties were investigated. The single‐ and triple‐layer electroluminescent (EL) devices with configurations of ITO/polymer/Al and ITO/polymer/OXD‐7/Alq3/Al were fabricated. They exhibited blue emission at 470 nm for OXA‐PPV1 and green emission at 560 nm for OXA‐PPV2. The turn‐on voltages of triple‐layer device were 11 V for OXA‐PPV1 and 8 V for OXA‐PPV2. The triple‐layer EL devices showed much better performance than did the single‐layer devices. The spectra indicated energy transfer occurred from segments of side chain to polymer backbone. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 422–428, 2002  相似文献   
106.
侯和峰  田辉  陈玉清 《陶瓷学报》2006,27(3):291-295
用氨水做催化剂配制碱溶胶,用盐酸做催化剂配制酸溶胶,在酸、碱混合溶胶中添加聚丙稀酸(PAA)引发相分离,通过添加不同含量的PAA,制备出具有不同粗糙度的透明薄膜,随后经过三甲基氯硅烷(TMCS)修饰,具有疏水性能和不同的疏水效果。  相似文献   
107.
聚氨酯/聚丙烯酸酯复合乳液的研制进展   总被引:21,自引:0,他引:21  
侯青顺  张剑秋  张翔飞 《化工进展》2002,21(11):831-835,850
综述了近年来聚氨酯-丙烯酸酯(PUA)复合乳液研究的新进展,总结介绍了各类聚氨酯-聚丙烯酸酯复合乳液(PUA共混复合乳液、PUA复合核/壳乳液、互穿网络PUA复合乳液)的制备方法和性能特点。并对该领域进一步的发展作了展望。  相似文献   
108.
本文报道了用气相色谱法同时测定油墨中的正丁醇、丁酮、甲苯、乙酸丁酯、二甲苯、环己酮,这方法具有良好的精密度、回收率和线性关系,测定了四种油墨所含的溶剂。  相似文献   
109.
Summary: Poly(ethylene 2,6‐naphthalate) (PEN) can crystallize either from the glassy state or from the melt state. When crystallized from the glassy state, the sample was quenched from the melt in liquid nitrogen and then annealed at certain crystallization temperatures. When crystallized from the melt state, the sample was cooled to a preset temperature from the melt and then annealed for a certain time. The crystal modifications, morphologies and melting behaviors of PEN were investigated by means of wide‐angle X‐ray diffraction (WAXD), polarized optical microscopy (POM), small‐angle light scattering (SALS) and differential scanning calorimetry (DSC). The results show that an α crystal modification of PEN was obtained when PEN crystallized from the glassy state, whilst a β crystal modification was obtained when PEN crystallized from the melt state at a higher temperature. An hedritic morphology of PEN crystal was obtained with only one melting peak observed in DSC curves when PEN was crystallized at a higher temperature from either the glassy state or the melt state. The α crystal modification could also be obtained when PEN was crystallized at a lower temperature from the melt. Spherulitic or banded spherulitic morphologies of PEN crystals, exhibiting multiple melting peaks in DSC curves, were observed when PEN was crystallized at a lower temperature. The multiple melting behaviors of PEN crystals may be associated with spherulitic structures composed of lamellae of varying thickness.

WAXD patterns of PEN isothermally crystallized from different states.  相似文献   

110.
以棉浆为原料,废盐酸为水解催化剂,所得合成革用微晶纤锥素增粘剂的质量指标达到了德国和日本同类产品的标准。  相似文献   
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