碳酸钾

Poly with sulfonic acid groups were readily synthesized with biphenol and 1,3-bis(4-fluorobenzoyl)benzene in the presence of excess potassium carbonate followed by sulfonation with chlorosulfonic acid.

以二氯二苯甲烷和2，6-二甲基苯酚为原料合成了含有阻碍基团的双酚单体，用此双酚单体和1，3-二(4-氟苯甲酰基苯)在无水碳酸钾存在的条件下反应制得聚芳醚酮，然后用氯磺酸磺化，控制反应条件，使磺酸基团恰好进入苯环对位，制得新型结构的磺化聚芳醚酮。

This is probably due to the geometry of the intermediate. 3. The cyclization of carbodiimide 2 with 1H-1, 2, 4-triazole in presence of solid potassium carbonate was studied firstly. The interesting color change was observed during the reaction process. The condition for cyclization was researched.

首次研究了碳二亚胺2与1H-1，2，4-三唑在固体碳酸钾存在下的成环反应，结果表明该反应仅生成1-N产物，而且在反应过程中出现了有趣的颜色变化，研究了该成环反应的条件。

The method comprises following steps: taking diphenol and 3- trifluoromethyl- 4- chloronitrobenzene as raw material, salt precipitating for diphenol and potash, refluxing with water- containing toluene, reacting with 3- trifluoromethyl- 4- chloronitrobenzene and getting dinitro monomer; taking dinitro monomer, ferro powder and HCl as raw material, ethanol and water as disslovant for refluxing and ethanol recrystallization, getting fluorine- containing aromatic diamido monomer.

合成方法是以二酚与3-三氟甲基-4-氯硝基苯作原料，先将二酚与碳酸钾成盐，甲苯带水回流反应，然后与3-三氟甲基-4-氯硝基苯反应制得二硝基单体；再以二硝基单体，铁粉，HCl为原料，乙醇和水做溶剂，回流反应、乙醇重结晶，得到含氟芳香二胺基单体。

The volume ratio of furaldehyde to acetic anhydride is 1∶2; the mole ratio of furaldehyde with anhydrous potassium carbonate is 1.00∶0.54. The best phase transfer catalyst is PEG1000, the mass ratio of PEG1000 with furaldehyde is 4.3%, the reaction time is 11 min, the reaction power of microwave is 260 W. The yield ofα-furanacrylicacid is up to 72.3% under these reaction conditions.

研究结果表明：在微波辐射功率为260 W、微波反应时间为11 min、以聚乙二醇1 000(PEG1000)为相转移催化剂，糠醛与乙酐的体积比为1∶2，糠醛与无水碳酸钾的量比为1.00∶0.55时，α-呋喃丙烯酸的产率为72.3%。

Study on different methods of iodomethane s preparation;2. The carbonyl group of DMC is formed by CO_2 insertion, and the two methyl groups of DMC are from methanol and iodomethane , respectively.

结果表明，固体碱碳酸钾催化剂直接参与了DMC的合成过程，DMC分子中的羰基由CO2插入甲醇后形成，两个甲基分别来源于甲醇和碘甲烷。

Bis-imidazoline was prepared from triethylene tetraamine and N,N-dimethylformamide dimethyl acetal at 85℃ for 2 h with toluene as solvent, with a yield of 90.4%. The reaction of bis-imidazoline with 1,2-dibromoethane and potassium carbonate in acetonitrile provided with a monobromide salt yield of 78.7%. Hydrolysis of monobromide salt under aqueous causic solution formed 1,4,7,10-tetraazzcyclododecane in a 74.2% yield.

用甲苯作溶剂，使三乙烯四胺和N，N-二甲基甲酰胺二甲基缩醛在85℃反应2 h，得到中间体双咪唑啉，产率90.4%，在乙腈溶剂中，碳酸钾存在下，双咪唑啉和1，2-二溴乙烷进行扩环反应，得到环状中间体一溴盐，产率78.7%，一溴盐经碱性水解2 h，得到1，4，7，10-四氮杂十二烷，产率74.2%。

The compound of BNTMBP wassynthesized by the condensation reaction between 4-chloronitrobenzene (4CNB) and 4, 4'-dihydroxy-3, 3', 5, 5'-tetramethyl biphenyl in the presence of potassium carbonate in the mixture solvents of N, N-dimethylformamide and tolune.

4， 4'-二羟基－3， 3'， 5， 5'-四甲基联苯、4-氯硝基苯(4CNB)和碳酸钾在N， N-二甲基甲酰胺和甲苯的混合溶剂体系中回流反应，合成得到了4， 4'-双（4-硝基苯氧基）－3， 3'， 5， 5'-四甲基联苯；随后，在Pd/C-水合肼的还原体系中，被进一步还原，得到了4， 4'-双（4-氨基苯氧基）－3， 3'， 5， 5'-四甲基联苯。

Wedgeplug O-Seal plug valves with their positive, no-leak features are not only recommended as the best general purpose valves for handling hydrocarbons, vegetable oils, solvents, etc., but are ideal for such tough service as butane, propane, butadiene, acetone, ethyl alcohol, ammonia, anhydrous ammonia, benzene, vinyl chloride, dry chlorine, Dowtherm, ethane, ethylene, hydrogen chloride, napthalene, oxygen, hydrogen, phthalic anhydride, dry phosgene, phosphoric acid, potassium carbonate, styrene, molten sulphur, sulphur dichloride and related services within a temperature range from -300oF to + 450oF within pressure limits of the valves.

楔塞O形密封旋塞阀具有积极的、无泄漏特性，不但是最好的通用的阀门，用于处理碳化氢，植物油，溶剂等，还特别适用于严酷的应用环境，如丁烷，丙烷，丁二烯，丙酮，乙醇，氨，无水氨，苯，氯乙烯，干氯，道氏热载体，乙烷，乙烯，氯化氢，萘，氧，氢，邻苯二甲酸酐，干碳酰氯，磷酸，碳酸钾，苯乙烯，融化硫，二氯化硫，以及温度在-184oC至232oC之间，压力在阀门额定压力等级范围内的有关应用。

The heat transfer performance of the umbrella-plate falling film evaporator was studied, water and concentration of 5%-40% potash was used as medium in this paper.

本文以水和5％～40％的碳酸钾溶液为工作介质，对伞板式降膜蒸发器的传热性能进行了实验研究。

Once the salts melt, a gray-white substance is left. This is potash.

一旦黑盐熔化，就会剩下一种灰白色的物质，这就是碳酸钾。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。