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1.
改变传统合成工艺,在高温高压无催化剂条件下,合成了无金属杂质的高邻位高分子量热塑性酚醛树脂。考察了苯酚与甲醛加成缩合反应过程中原料种类、原料配比、反应温度及反应压力等因素对酚醛树脂结构性能的影响。通过软化点测试仪、核磁共振谱仪等研究了酚醛树脂合成过程中各个参数对酚醛树脂结构性能的影响。在酚/醛比为1:0.7,210℃、...  相似文献   

2.
生物可降解高吸水性非织造布的研制   总被引:5,自引:0,他引:5  
用聚丙烯酸接枝淀粉浆液,在PVA非织造布上形成吸水树脂,从而得到高吸水性非织造布。对接枝单体的比例、交联条件、浸轧量及非织造布规格等因素对高吸水非织造布吸水性能的影响进行了讨论了并测定了其生物降解性能。  相似文献   

3.
用H_2S、NaOH、p-C_6H_4Cl_2为原料,以Na_3PO_4作助剂,在六甲基磷酰三胺中进行常压缩聚反应4~5 h,得到线型、结晶性的高分子量聚苯硫醚。熔点>290℃,热分解温度>500℃,熔融低切变粘度为0.30~68.0×10~3Pa(303℃测定)。产品直接作抽丝试验,得到高分子量聚苯硫醚纤维。本法设备简单、操作容易、反应体系活性高、溶剂稳定。  相似文献   

4.
设计利用弹性体聚合物改性沥青料,大幅提升沥青黏韧性,并分析改性组分(如改性剂、相容剂、稳定剂等)、以及改性工艺(如发育温度、发育时间)对改性沥青性能的影响机理,进而对针入度、软化点、老化前后延度、60℃动力粘度、(135℃、175℃)运动黏度、离析等指标进行系统分析,对高黏改性沥青性能进行优化设计,并利用荧光显微观察聚...  相似文献   

5.
高硫石油焦制备高储气性能天然气吸附剂   总被引:3,自引:3,他引:0  
以高硫石油焦为原料,KOH为活化剂,十二烷基苯磺酸钠(SDBS)为表面活性剂制备天然气吸附剂,分析了高硫焦基吸附剂的孔结构和孔分布特征,讨论了高硫焦制备吸附剂的活化机理。结果表明,预活化中加入表面活性剂SDBS可提高KOH与原料的混合均匀度,对活化效果有利。最优活化条件下制备的吸附剂样品GSR3和GSR4的微孔容积分别达到1.0985cm3·g-1 和1.3193cm3·g-1,孔径分布集中在0.9nm~1.5nm;在25℃、充放气压力3.5MPa和0.1MPa下,GSR3、GSR4对甲烷的质量吸附量分别达到0.139和0.145,有效体积脱附量达到111和115。粉体高硫焦基吸附剂的性能非常接近于低硫焦基吸附剂。  相似文献   

6.
为深入了解高硫石油焦在工业应用高温工况下的热解过程以及硫的析出特性,本研究采用高温固定床对青岛高硫石油焦进行了高温(900-1500℃)热解实验,考察了高温热解下热解气体释放规律,热解过程中焦的物理孔隙结构以及化学特性的演变,并对热解过程中硫的析出与演变特性进行了研究。结果表明,随着热解温度的升高,石油焦热解气中的H_2含量逐渐增加,CO含量变化不大,CH_4与CO_2含量则逐渐下降;热解焦的比表面积与平均孔隙均随热解温度的升高有所增加,颗粒的表面形态则受温度影响较小;热解温度的升高会降低石油焦中含有的非定型碳比例,提高其微晶结构的有序性以及石墨化程度;热解焦的气化活性随热解温度的升高先降低后升高,在1100℃附近有最小值; 1500℃高硫石油焦硫元素析出率达81.34%,仅少量硫醇类有机硫和噻吩环内的硫元素得以残存。  相似文献   

7.
高山地榆(Sanguisorba alpina Bge)是蔷薇科地榆属植物,民间用于止血、止吐、抗菌、解毒.本文报道从其根粉60%乙醇提取物中分离得到的新三萜皂甙,命名为高山地榆甙(alpinoside,1). 化合物1为白色粉末,m.p.:247-249.5℃,[α]15D:+7.5°(C,0.2;MeOH).IRvKBrmax(cm-1)示有羟基(3457)、酯羰基(1738)、末端双键(1702,882)和三取代双键(1656).HRMS给出其甙元M+为m/z470.3324.示其分子式为C30H46O4(计算值:470.3396).碎片峰m/z:452(8),424(14),246(15),223(25),201(100),187(55),结合12C NMR(见表1)表明1为  相似文献   

8.
高折射率高透明性半脂环聚酰亚胺的合成与性能   总被引:1,自引:0,他引:1  
采用脂环二酐单体2,3,5-三羧基环戊烷基乙酸二酐(TCAAH)分别与两种含硫芳香族二胺单体,4,4′-双(4-氨基苯硫基)二苯硫醚(3SDA)与2,7-双(4-氨基苯硫基)噻蒽(APTT)通过两步法制备了两种半脂环聚酰亚胺(PI).制备的PI薄膜在可见光波长范围内(400~700 nm)具有优良的透明性,400 nm处的透过率超过85%.此外,该系列薄膜还具有良好的耐热稳定性,氮气中的起始热分解温度超过480℃,玻璃化转变温度超过250℃.PI薄膜在632.8 nm处的折射率大于1.68,双折射小于0.006.为了进一步提高PI薄膜的折射率,初步考察了PI前体溶液聚酰胺酸(PAA)与高折射率无机TiO2纳米粒子的复合工艺.结果表明,PI-TiO2薄膜同样具有良好的透明性,632.8 nm处的折射率达到1.76.  相似文献   

9.
以过硫酸铵为引发剂,N,N’-亚甲基双丙烯酰胺为交联剂,制备氧化淀粉―丙烯酸―丙烯酰胺高吸水性树脂,并采用红外光谱、X射线衍射等手段对产品的结构进行表征。通过单因素实验优化其制备工艺,最佳工艺条件为:氧化淀粉基体用量为50%,丙烯酸/丙烯酰胺质量比为4∶1,丙烯酸中和度为70%,引发剂过硫酸铵用量为0.5%,交联剂N,N’-亚甲基双丙烯酸胺用量为0.15%,反应温度为80℃,反应时间为3 h。此条件下,氧化淀粉基高吸水性树脂的吸水率达到972.4 g/g。  相似文献   

10.
高灰煤小型流化床混合气催化气化研究   总被引:4,自引:4,他引:0  
在内径28mm流化床中,对阳泉高灰煤在碱性催化剂(固碱和黏胶废碱液)作用下进行了混合气(空气/水蒸气)催化气化研究,两种碱性催化剂的适宜添加量均为6%。不加催化剂,气化温度830℃~900℃与900℃~920℃下,气化反应的表观反应级数n分别约为2/3与1/3;有催化剂(3%固碱)时,表观反应级数有两个明显的温度段,在830℃~860℃,催化气化的表观反应级数n=1;在860℃~920℃,催化气化的表观反应级数为n=1/3。  相似文献   

11.
利用手持技术改进测定乙醇分子结构实验   总被引:1,自引:0,他引:1  
利用压强传感器代替排水集气法,改进测定乙醇分子结构实验的仪器装置,并探索最佳反应条件。另外,设计两个空白实验,结合压强变化曲线对实验误差进行相关讨论。  相似文献   

12.
13.
由于石化行业的生产需要,其材质的使用具有多样性和广泛性,经常会出现顾客委托的测试样品的一个或几个元素跨越光谱仪现有测试程序测量范围的情况。本法通过对光谱仪测试原理的认识,根据光谱仪的测试能力及标样的采集,实现了一个或几个元素测量范围的扩展,并对其测量的影响因素进行了研究。  相似文献   

14.
The oxygen quenching rate constants for singlet and triplet excited states of the dimethyl ester of mesoporphyrin IX increase with decreasing viscosity of the medium and reach a maximum at a viscosity of approximately 0.4 mPa·sec, after which the rate constants begin to decrease. The drop in rate constant with increasing fluidity of the medium may be related to a nonequilibrium character of the elementary act in the interaction of the reactants in the solvent cage. In viscous media such as isopropyl alcohol, isobutyl alcohol, and isoamyl alcohol, the reaction radius is greater than the sum of the radii of the reacting particles. The long-range character of these processes is due to the relatively weak dependence of the quenching probability on distance.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 25, No. 2, pp. 161–167, March–April, 1989.  相似文献   

15.
The spectral-polarization characteristics of absorption and phosphorescence of molecules of the initial form of nitro-substituted indolinospirobenzothiopyran were studied in oriented polyethylene films and in solutions with different polarity. An oscillator model of the electron transitions responsible for the formation of absorption and luminescence spectra was suggested. It was established that the principal differences in the spectral and photophysical properties of the compound studied and its oxygen-containing analog are associated with the fact that the electronegativity of the S atom is lower than that of the O atom. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1146, June, 1997.  相似文献   

16.

The heats of detonation of 20 simple high explosives and explosive mixtures were determined by means of an adiabatic detonation calorimeter designed by the authors. The results indicated that the performance of the instrument was reliable and the experimental data were very accurate. For explosive mixtures, there was a linear accumulative relationship between the heats of detonation of the explosive mixture and its components. Accordingly, the heats of detonation of explosive mixtures could be calculated directly from the heats of detonation of simple explosives and the characteristic heats of other components. The experiments showed that the gold or brass shell of the cylindrical charge could be substituted by a thick-walled porcelain shell, which had the advantage of cheapness.

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17.
实验教学目的是从解决实际问题出发,以实验技术训练和实验设计思想培养为目标。介绍了将单一的物质分配系数测定实验改进为综合实验,提高了实验效果及实验资源利用率。  相似文献   

18.
The compositions of the neutral diterpenoids of the oleoresins of five species of conifers growing in the Transcarpathia have been studied. It has been found that the oleoresins ofAbies alba M.,Larix decidua M., andPicea excelsa L. contain more than 50% of neutral diterpenoids. The group and qualitative compositions of the oxygen-containing diterpenoids have been determined. In the oleoresins ofAbies alba,Picea excelsa, andPicea abies tertiary alcohols — cis-abienol and isocembrol — predominate, while inLarix decidua the main component is the hydroxy ester larixyl acetate. Primary alcohols related to the resin acids have been found in all the oleoresins investigated. Features of the distribution of diterpenoids according to the species of conifers have been revealed. The results obtained are necessary for the chemotaxonomy of conifers of the family Pinceae.Novosibirsk Institute of Organic Chemistry, Siberian Branch, Academy of Sciences of the USSR. Translated from Khimiya Prirodynkh Soedinenii, No. 6, pp. 812–816, November–December, 1988.  相似文献   

19.
Sets of hydrogen molecule equivalents have been developed which permit the calculation of hydrogenation of different types of carbon-carbon bonds from ab initio total energies (3-21G and 6-31G* basis sets, and, to a more limited extent, for MP2/6-31G* data) of reactants and products. The calculated enthalpies of hydrogenation are in good agreement with experiment for unstrained molecules, with average errors on the order of 2 kcal/mol. The 6-31G* equivalents allow the enthalpies for strained molecules to be calculated accurately, but the 3-21G equivalents do not. The equivalents for both basis sets have been tested by calculating the enthalpies of hydrogenation of carbon-carbon bonds in nitrogen- and oxygen-containing organic molecules, free radicals, and classical carbocations. The results are in good agreement with experiment in most cases.  相似文献   

20.
非那雄胺能抑制5α-还原酶的活性,明显降低二氢睾酮水平,是一种治疗良性前列腺增生的有效药品。该合成工艺以甾烯酮酸为原料,将其与氯化亚砜反应,无须分离即与叔丁胺反应得17β-酰胺化合物,再氧化开环,环合,氢化,脱氢合成了非那雄胺。经元素分析、IR、1HNMR、13CNMR、MS分析表征了其结构。该法无须使用昂贵的2,2-二吡啶二硫化物和剧毒药品苯亚硒酸酐,且以乙酸铵代替氨气,降低了对设备的要求和腐蚀,更适用于工业生产。  相似文献   

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