二(二甲苯基)丙烷合成工艺的研究

二氯丙烷(DCP)与二甲苯在混合金属氯化物催化剂(HD90)作用下合成二(二甲苯基)丙烷,生产过程简单,产品收率高。在60—80℃的温度下,二甲苯与二氯丙烷摩尔比为6∶1,HD用量50克/摩尔DCP的条件下反应5—6小时,二(二甲苯基)丙烷的收率可达88％以上。     

Performance of the polymer- and oxide-supported triphase catalysts and effect of ultrasound on their stabilities

In this study, several trialkylamines were immobilized on chloromethylated polystyrene (CMPS), silica gel, and alumina to prepare triphase catalysts for catalyzing the etherification reaction of allyl bromide (the organic reactant) and sodium phenolate (the aqueous reactant). The reactor was agitated mechanically or with the aid of ultrasonic vibration. Performances of the prepared catalysts were compared, and the effect of imposing ultrasound was investigated based on the activity, selectivity, and stability of the catalyst. Experimental results show that tri-n-propylamine is the best active species when CMPS is used as the support, while tri-n-butylamine is the best when SiO₂ and Al₂O₃ are employed as the supports. The CMPS-supported catalyst is far better than the SiO₂- and Al₂O₃-supported catalysts in activity and selectivity but not in stability. Imposing the ultrasound can effectively increase the reaction rate. Mechanical agitation at a low speed with the imposition of ultrasonic vibration not only results in a conversion slightly higher than the case with a high mechanical agitation speed without ultrasonic vibration, but also gives a constant stability for the CMPS-supported catalyst.     

苯乙酸溶解度测定及提取工艺研究

为了提取6-氨基青霉烷酸(6-APA)、7-ADCA生产过程中产生的副产物苯乙酸,采用物理法测定了苯乙酸在水、水-乙醇、水-丙酮中的溶解度及其在水中的溶解速率,由此确定了水法多次提取的工艺方案。结果表明,在提取温度(60±2)℃,时间10~15 m in,水用量1 500 mL,提取次数3~4次时,苯乙酸收率为90.8%,纯度为99.3%。该法污染少、成本低,所得PAA产品质量好。     

亚砜基改性纤维素膜的SO2气体渗透性能研究

分别使用二甲基亚砜浸泡的物理方法及苯基乙烯基亚砜加成的化学方法对纤维素膜进行了改性,并对改性膜的性能进行了测试.结果表明改性后纤维素膜仍为致密结构,SO2的渗透性能及其对N2的分离性能明显提高,其中改性液中添加二甲基亚砜的均相化学加成反应所得的改性膜具有较好的SO2渗透稳定性.     

新显色剂4—（2—苯并噻唑偶氮）邻苯二酚—钼（Ⅵ）—OP体系的分光光度研究

在ｐＨ５．０～５．７范围内，新显色剂４－（２－苯并噻唑偶氮）邻苯二酚（ＢＴＡＰＣ）与钼（Ⅵ）和非离子表面活性剂ＯＰ反应，形成稳定的、带负电荷的、紫红色三元胶束配合物。该配合物中Ｍｏ（Ⅵ）与ＢＴＡＰＣ的组成比为１∶２；其λｍａｘ为５６０ｎｍ，对比度（Δλ）为１２８ｎｍ；在２０℃、ｐＨ５．２和μ０．１时，配合物的表观稳定常数为３．０２×１０１０，表观摩尔吸光系数ε５６０为８．１１×１０４Ｌ·ｍｏｌ－１·ｃｍ－１，真实ε５６０为７．６７×１０４Ｌ·ｍｏｌ－１·ｃｍ－１。钼含量在０～０．７２ｍｇ／Ｌ范围内遵从比耳定律。建议了配合物的结构。本法简便、快速、准确，用于合金钢试样中痕量或小量钼的测定，取得了满意的结果。     

一类含查尔酮结构的光敏性二胺的合成研究

以醛、酮为原料经羟醛缩合反应合成了具有一类含查尔酮结构的光敏性二胺:1-(3-氨基苯基)-3-(4-氨基苯基)-2-丙烯-1-酮与对-二(间氨基肉桂酰)苯.通过优化实验得到最佳的合成工艺为:醛、酮在温度为0℃下,以乙醇为溶剂,氢氧化钠为催化剂,进行羟醛缩合反应3h.收率可达到86%,经液相色谱分析其纯度分别为99.92%,99.91%,紫外可见最大吸收波长分别为349nm、361nm.所得方法操作简便,收率较高,原料易得.并用元素分析、核磁共振、红外光谱等手段对产物的结构进行了表征.     

苯氨基甲酸酯催化合成研究进展

综述了国内外苯氨基甲酸酯合成方法和催化剂的研究进展,重点阐述了近年来以苯胺和碳酸二甲酯(DMC)为原料,合成苯氨基甲酸甲酯(MPC)催化剂的研究进展.同时对今后催化合成路线的研究和发展进行了讨论和分析,由苯胺和DMC合成MPC,副产物甲醇回收合成DMC,是零排放绿色工艺,其研究方向是开发出活性和选择性高的负载型催化剂.     

Effect of nutrient seed coating on the emergence of wheat and oats

A series of experiments was conducted under controlled soil moisture and temperature conditions in a growth chamber to examine the effect of a range of nutrient seed coatings on the emergence to wheat (Triticum aestivum L. cv. Kite) and oats (Avena sativa L. cv. Blackbutt) sown in a coarse sandy loam soil. Final emergence of oats was not reduced by a coating containing 10 kg P ha^–1 (as monocalcium phosphate [MCP]) whereas the same coating reduced wheat emergence by 15%. The emergence of both wheat and oats was severely reduced by urea coatings (supplying 10 kg N ha^–1) to 33 and 13% respectively; this injury was lessened markedly by the inclusion of phenyl phosphorodiamidate (PPD) in the urea coatings at 1% (w/w) (emergence increased to 66 and 56% respectively).Low soil moisture (67% of field capacity [FC]) resulted in almost no emergence of wheat coated with urea (± bentonites of different pH). In soil at FC, the addition of bentonite of pH 5 (B5) to urea coatings permitted greater emergence (54%) than when bentonite of pH 9 (B9) was added (32%) which, in turn, permitted greater emergence than urea coating alone (10%). When PPD and bentonite (B5 or B9) were combined either singly or together with urea in seed coatings, PPD was more effective than either of the bentonites in reducing injury and masked the slight positive effect of B5.Coatings containing various combinations of N and P sources (at 3.6 and at 8 kg ha^–1 respectively) all reduced the emergence of wheat compared to raw seed (91% emergence). When applied alone, MCP was least damaging (74%); the combination of MCP with ammonium sulfate (AS) caused somewhat more injury (68%) whilst combination with calcium nitrate (CN) caused most injury (29%). In contrast, CN alone caused relatively little damage (73%) whilst AS alone was more damaging (50%). There was no significant regression found between percentage emergence and either the calculated partial salt index or the pH of the nutrient coatings. Further work is needed to examine the mechanisms of injury due to nutrient seed coatings so that safe but effective formulations can be developed.     

双(4-胺基苯基)-苯基磷酸酯的合成及其性能研究

以对硝基苯酚和苯基二氯磷酸酯为原料,采用两步法合成了双(4-胺基苯基)-苯基磷酸酯(BAPP)含磷二胺固化剂,用红外光谱法对合成产物进行了分析和表征。固化反应动力学分析表明,BAPP与环氧树脂的反应活性较DDM的反应活性略高。BAPP与环氧树脂的固化产物热失重分析表明,在低温区主要是有机磷化合物的分解,在高温区主要是基体主链的断裂;与DDM的环氧固化产物相比较,BAPP与环氧树脂的固化产物有较高的成炭率,极限氧指数(LOI)为34,BAPP对固化产物的玻璃化温度影响不大。     

Fate of nitrogen fertilizer applied to lowland rice on a Sulfic Tropaquept

A field experiment was conducted on an acid sulfate soil in Thailand to determine the effect of N fertilization practices on the fate of fertilizer-N and yield of lowland rice (Oryza sativa L.). A delayed broadcast application of ammonium phosphate sulfate (16-20-0) or urea was compared with basal incorporation of urea, deep placement of urea as urea supergranules (USG), and amendment of urea with a urease inhibitor. Deep placement of urea as USG significantly reduced floodwater urea- and ammoniacal-N concentrations following N application but did not reduce N loss, as determined from an¹⁵N balance, in this experiment where runoff loss was prevented. The urease inhibitor, phenyl phosphorodiamidate (PPD), had little effect on floodwater urea- and ammoniacal-N, and it did not reduce N loss. The floodwater pH never exceeded 4.5 in the 7 days following the first N applications, and application of 16-20-0 reduced floodwater pH by 0.1 to 0.3 units below the no-N control. The low floodwater pH indicated that ammonia volatilization was unimportant for all the N fertilization practices. Floodwater ammoniacal-N concentrations following application of urea or 16-20-0 were greater on this Sulfic Tropaquept than on an Andaqueptic Haplaquoll with near neutral pH and alkaline floodwater. The prolonged, high floodwater N concentrations on this Sulfic Tropaquept suggested that runoff loss of applied N might be a potentially serious problem when heavy rainfall or poor water control follow N fertilization. The unaccounted-for¹⁵N in the¹⁵N balances, which presumably represented gaseous N losses, ranged from 20 to 26% of the applied N and was unaffected by urea fertilization practice. Grain yield and N uptake were significantly increased with applied N, but grain yield was not significantly affected by urea fertilization practice. Yield was significantly lower (P = 0.05) for 16-20-0 than for urea; however, this difference in yield might be due to later application of P and hence delayed availability of P in the 16-20-0 treatment.