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1.
无卤阻燃剂间苯二酚双(二苯基)磷酸酯的合成及表征   总被引:1,自引:0,他引:1  
用路易斯酸作为催化剂,用间苯二酚、三氯氧磷和苯酚作为原料合成出了间苯二酚双(二苯基)磷酸酯(RDP).研究结果表明,最好的催化剂为MgCl<,2>,并且其最佳的用量为间苯二酚用量的1%(mol).所得产物经过红外光谱、高效液相色谱和酸度的表征并对其结果进行了讨论,热失重分析表明产物的5%热失重分解温度为315℃,可作为阻燃工程塑料的阻燃荆.  相似文献   

2.
间苯二酚-甲醛有机气凝胶的结构控制研究   总被引:8,自引:0,他引:8  
以间苯二酚(Resorcinol)-甲醛(Formaldehyde)为原料,用溶胶-凝胶法和超临界干燥工艺制备了纳米多孔RF有机气凝胶。系统研究了原料配比、催化剂的使用、反应温度及溶剂用量等因素对RF气凝胶凝结时间和结构的影响,可以实现对该材料的结构进行纳米尺寸上的控制,从而为该材料的应用开发奠定了基础。  相似文献   

3.
间苯二酚—甲醛有机气凝胶的结构控制研究   总被引:3,自引:0,他引:3  
以间苯二酚-甲醛为原料,用溶胶-凝胶法和超临界干燥工艺制备了纳米多孔RF有机气凝胶,系统研究了原料配比,催经剂的使用,反应温度及溶剂用量等因素对RF气胶胶凝结时间和结构的影响,可以实现对该材料的结构进行纳米尺寸上的控制,从而为该材料的应用开发遵定了基础。  相似文献   

4.
采用一维中红外(MIR)光谱技术开展了间苯二酚的结构研究。间苯二酚的红外吸收模式包括:ν_(OH-间苯二酚)、ν_(CH-间苯二酚)、ν_(C=C-间苯二酚)、β_(OH-间苯二酚)、ν_(C-O-间苯二酚)、β_(CH-间苯二酚)、γ_(CH-间苯二酚)和δ_(环-间苯二酚)。采用一维变温中红外(TD-MIR)光谱,进一步开展了间苯二酚的热稳定性研究。实验发现:在293~453 K的温度范围内,随着测定温度的升高,间苯二酚的主要官能团对应的吸收频率及强度均有明显的改变,间苯二酚的热稳定性进一步降低,而383~393 K是一个临界温度区间,并进一步进行了机理研究。研究进一步证明一维MIR光谱和一维TD-MIR光谱在重要的精细化工中间体(间苯二酚)结构及热稳定性分析中的重大作用。  相似文献   

5.
2-氯-4,6-二硝基间苯二酚的合成   总被引:1,自引:0,他引:1  
以4,6-二硝基-1,2,3-三氯苯为原料,采用水相碱性水解法合成了2-氯-4,6-二硝基间苯二酚,并采用了元素分析,红外光谱,质谱和高效液相色谱对合成的产品进行了表征。采用正交实验法对合成2-氯-4,6-二硝基间苯二酚的工艺进行了研究,确定了最佳工艺条件,在此条件下得到的2-氯-4,6-二硝基间苯二酚的收率为96.37%,纯度为96.89%。对水解产品重结晶用溶剂进行了考察,确定了正丁醇为水解产品重结晶用溶剂,重结晶产品的收率为90.02%,纯化后产品的纯度为99.56%。  相似文献   

6.
4,6-二氨基间苯二酚(DAR)盐酸盐单体的制备是合成高性能纤维聚对苯撑苯并双口恶唑(PBO)的关键,而间苯二酚乙酰化、肟化法是高效制备该单体的重要方法。新方法采用浓硫酸作为催化剂改进二肟中间体Beckmann重排、水解制备DAR的过程,成功制备得高纯度的DAR单体。并通过对温度、浓硫酸使用量等影响反应的主要因素进行比较研究,总结出浓硫酸催化制备DAR的合适条件。该方法不仅有效解决了使用多聚磷酸制备DAR时操作复杂等问题,而且节约了成本,缩短了反应时间。  相似文献   

7.
以间苯二酚和甲醛为原料,溴化十六烷三甲基铵为催化剂,通过反相悬浮聚合法成功制备了炭气凝胶微球.研究了反应体系的黏度、酸度、温度以及反应中间产物紫外光谱的变化情况,探讨该凝胶反应的作用机理.结果表明:凝胶反应是一个酚醛缩合过程,其反应历程可以分为线性缩聚、交联、胶粒生长和宏观凝胶化四个阶段.  相似文献   

8.
二甲基二酚羟基有机烷氧基硅烷的合成研究   总被引:3,自引:1,他引:2  
以二甲基二乙氧基硅烷和间苯二酚为原料,在Na的催化作用下通过酯交换反应制得二甲基二酚羟基有机硅烷中间体,研究了反应温度、反应时间以及催化剂用量对产物性能及收率的影响;并用IR、VPO、LU/MS对其进行了表征。  相似文献   

9.
以2-氯-4,6-二硝基间苯二酚为原料,Pd/C为催化剂,在磷酸水溶液体系中加氢,使生成的4,6-二氨基间苯二酚(DAR)直接成盐,经过一系列的分离提纯得到4,6-二氨基间苯二酚二磷酸盐(DAR·2H3 PO4).通过FT-IR、元素分析、高效液相色谱等分析,确定产品为DAR·2H3PO4,最高收率为98.21%,HPLC纯度为97.25%.且发现用3%H2O2处理后的活性炭制得的催化剂活性和稳定性最好,可媲美同类商业化催化剂,使用后可洗涤再生,循环10以上催化活性未见降低.  相似文献   

10.
以三聚氰胺、间苯二酚、甲醛为原料,采用溶胶-凝胶法、冷冻干燥等步骤制备出三聚氰胺-间苯二酚-甲醛(MR)干凝胶;并以所制炭气凝胶为载体浸渍硝酸钴,经氮气中高温炭化,得到钴复合氮掺杂的炭气凝胶。考察间苯二酚和三聚氰胺比例、凝胶pH值及炭化条件等对气凝胶结构和催化氧还原活性的影响,采用XRD、XPS、低温氮气吸脱附等方法研究催化剂的结构。随pH值增加,MR气凝胶的介孔分布向小孔移动;当M/R物质的量比为6∶1时,其介孔分布为3.0~4.0 nm。钴复合炭气凝胶多孔结构中存在均匀分布Co金属颗粒和管状炭,Co金属颗粒粒径随炭化温度升高而增加。采用旋转圆盘电极研究催化剂在0.5mol/L H2SO4溶液中的电化学性能,结果表明催化剂具有良好的氧还原活性。  相似文献   

11.
In this paper, we present a new method for inserting several triangulated surfaces into an existing tetrahedral mesh generated by the meccano method. The result is a conformal mesh where each inserted surface is approximated by a set of faces of the final tetrahedral mesh. First, the tetrahedral mesh is refined around the inserted surfaces to capture their geometric features. Second, each immersed surface is approximated by a set of faces from the tetrahedral mesh. Third, following a novel approach, the nodes of the approximated surfaces are mapped to the corresponding immersed surface. Fourth, we untangle and smooth the mesh by optimizing a regularized shape distortion measure for tetrahedral elements in which we move all the nodes of the mesh, restricting the movement of the edge and surface nodes along the corresponding entity they belong to. The refining process allows approximating the immersed surface for any initial meccano tetrahedral mesh. Moreover, the proposed projection method avoids computational expensive geometric projections. Finally, the applied simultaneous untangling and smoothing process delivers a high‐quality mesh and ensures that the immersed surfaces are interpolated. Several examples are presented to assess the properties of the proposed method.  相似文献   

12.
We associate a variety of innovations with the term "Industry 4.0". The pioneer of many 4.0 modifications forms the basisfor the trend towards the integrated di...  相似文献   

13.
A four-ball tester was used to evaluate the anti-wear performance of three kinds of organomolybdemun compounds in the engine oils, i. e., molybdenum dialkyldithiophosphate (MoDDP), molybdenum dialkyldithiocarbamate ( MoDTC), and sulphur and phosphorus freeorganomolybdeum (Molybdate). The results indicate that a low concentration of MoDDP doesn' t improve the anti-wear properties of the commercial engine oils, but a high concentration of MoDDP can obviously improve the anti-wear properties and the load-carrying capacity of the engine oils. MoDTC doesn' t improve the antiwear properties of the engine oils, but worsens the anti-wear properties of the oils. Signifi can timprove ment of frictional and wear characteristics is obtained with Molybdate added in the commercial engine oils and the formulated oils.  相似文献   

14.
ABSTRACT

The production of ferrous metal increased during the Roman Late Republican period, Principate and Empire. The direct bloomery process was used to extract the metal from its ores using slag-tapping and slag-pit furnaces. The fuel was charcoal and an air blast was introduced by bellows-operated tuyères. Iron formed as a bloom, often as a spongy mass of metal, which contained impurities from the smelting process, including unreacted ore, fuel, slag and fragments from the furnace walls, while the metal was often inhomogeneous with varied carbon contents. Blooms were either smithed directly into bars or ingots or they were broken up, which also allowed the removal of gross impurities and a selection of pieces with similar properties to be made. These could then be forge-welded together and formed into characteristically shaped ingots. Making steel in the furnace seems to have been achieved: it depended on the ore and the furnace and conditions within it. Surface carburization was also carried out. Iron and steel were used extensively in construction and for tools and weapons. Fire welding was often used to add pieces of steel to make the edges of tools and weapons, which could be heat-treated by quenching to harden them.  相似文献   

15.
16.
Standards are the basis for production enterprises to organize production, ex-factory inspection, trade (delivery) and technical exchanges, product certification, quality arbitration and supervision.……  相似文献   

17.
A flow calorimeter for enthalpy increment measurements on condensed gases is presented. A better knowledge of the properties of the liquefied natural gas is needed, and therefore a liquid loop has been designed for our flow calorimeter. The fluid loop in the calorimeter is designed in order to avoid the two-phase region, since two phases would give compositional disturbances in the measurements. The avoidance of the two-phase region is made possible by increasing the pressure of the test fluid after the measurement section, then heating the fluid at super-critical pressure past the critical point. Finally, the fluid is throttled to the low-pressure gas state at the inlet condition of the compressor that circulates the fluid. To perform the pressure increase, a new cryogenic pump has been designed. To evaluate the new equipment, measurements were taken on liquid ethane over the temperature range 146–256 K at pressure between 0.9 and 5.1 MPa.  相似文献   

18.
Al2O3-ZrO2 nanocomposites were developed starting with the solgel process. Composite alumina-zirconia nanopowders were synthesized from metallorganic precursors (Aluminium secondary butoxide and zirconium Iso propoxide) using the solgel process. The parameters affecting the synthesis—solvent, concentration of precursor, R/H ratio (i.e., dilution of water in solvent)—were varied as also the temperature and pH. BET and TEM were used to measure nanosize. Diffuse reflectance spectroscopy and also qualitative optical absorption led to identical particle size estimate. The variation of process parameters was used to study the effect and interdependence of process parameters. Artificial Neural Networks was used to rigorously analyze the process. Although this led to confirmation of interdependence of parameters, the presence of a single overwhelming solvent variable was also established. Then the optimal process was used to synthesize more nanopowder. To produce bulk nanocomposite the nanopowders were sintered by varying the temperature and time period. The sintered lithoids were probed with a vickers hardness tester to measure elastic modulus, hardness, and fracture toughness. The results showed high elastic modulus, modest hardness, and very high fracture toughness.  相似文献   

19.
The end of 2007, over 200 unit products of more than 80 Chinese firms have passed the quality grade certification for liquor products. These products involve distilled spirits, beer, wine, yellow wine, fruit syrup wine and others, and cover over 80% of the national top-branded liquor products.……  相似文献   

20.
Surface characterization and microstructure studies are performed on chemical vapor deposited (CVD) tungsten coating. There is about 2 μm thickness diffusion layer of tungsten in the molybdenum substrate. The thermal shock test shows tungsten coating has good adhesion with molybdenum substrate, but the elements of oxygen and carbon in the tungsten coating have the bad affection to the adhesion. The result of high-temperature diffusion experiment is the diffusion rate from molybdenum substrate to tungsten coating is faster.  相似文献   

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