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磷矿粉盐酸萃取液氟含量的研究 总被引:2,自引:0,他引:2
对盐酸与磷矿粉的萃取反应条件进行研究,实验结果表明,反应温度60℃,盐酸含量25%,盐酸以滴加方式与磷矿粉混合反应,萃取液中氟含量最低。经进一步除氟处理之后,制得饲料级磷酸氢钙 相似文献
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采用浓盐酸为催化剂,以三乙醇胺为主要原料经催化分子内脱水环合合成了吗啉乙醇.考察了催化剂种类、用量、反应温度和时间对转化率的影响,结果表明浓盐酸对本反应有较高的催化活性,在优化工艺下三乙醇胺转换率可达55%以上,产品经精馏提纯后含量在99%以上. 相似文献
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以L-脯氨酸和硫酸二甲酯合成了盐酸水苏碱.确定最佳工艺条件为:11.5 g L-脯氨酸、12.05 mol·L-1氢氧化钠220 mL和硫酸二甲酯21 mL在50~55℃下反应2.5 h,反应液以盐酸调pH值2~3.经结晶纯化后,盐酸水苏碱收率达95.2%,含量为99.4%. 相似文献
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采用盐酸、硝酸、硫酸等试剂分解试样,铅形成硫酸铅沉淀,过滤洗涤使硫酸铅沉淀与铜、锌、铁等金属离子分离,沉淀加NaAc-HAc缓冲液溶解,用EDTA标准液滴定测铅.滤液以水定容至100mL,用移液管分别分取2份部分溶液,1份溶液用碘量法测定铜.另1份溶液加过量氨水使锌离子与铁离子等分离,过滤洗涤,滤液用EDTA标准液滴定... 相似文献
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三唑酮在土壤中的降解产物和手性选择性 总被引:1,自引:0,他引:1
[目的]研究三唑酮农药在土壤中降解产物和代谢途径.[方法]在25℃下采用添加三唑酮农药试验,培养1个月.采用GC/MS全扫描模式分离和监测降解产物.[结果]三唑酮降解产物有三唑醇和三唑二醇化合物,其中三唑醇有立体选择体,在土壤中三唑醇的对映体选择值(EF)为3.5,三唑酮在不同酸碱性土壤中降解产物是相似的,不同含水量土壤中降解产物是不一样的,低含水量土壤未发现三唑醇,中含水量土壤中有三唑醇,高含水量土壤中有2个降解产物.[结论]在土壤中三唑酮的降解过程,水是关键作用之一. 相似文献
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Ammonium polyphosphate (APP) which was surface-modified with melamine (MA) and 2,4-toluene diisocyanate(TDI) in turn was used
as flame-retardant in linear low density polyethylene (LLDPE). Its water resistance in LLDPE was respectively evaluated with
its water-solubility, the limited oxygen index(LOI) changes and P content changes of the LLDPE which being immersed in water
180 h at room temperature. Its compatibility with LLDPE was observed with scanning electron microscope (SEM). As a result,
the water-solubility of the surface-modified APP reduced. When the LLDPE was treated with surface-modified APP, its LOI and
P content changes were less than that treated with unmodified-APP after being immersed in water. The surface-modified APP
was better compatible with LLDPE than unmodified APP. 相似文献
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杀菌剂噻菌灵在香菇上残留量测定 总被引:7,自引:1,他引:7
以丙酮作提取剂,经二氯甲烷萃取,用丙酮定容,然后用SIGMA-300型带NPD检测器的气相色谱仪测定。其测定结果的准确度和精密均符合残留量测定的要求。 相似文献
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提出了同向自洁型双螺杆挤出机端面非对称造型的新概念。以符合Carreau定律的纯黏性流体为加工对象,建立相应的数学模型。采用Polyflow软件,基于叠加网格技术,对两种螺杆造型端面内的周期性流动和混合情况进行数值模拟。将粒子示踪技术及分离尺度相结合,研究了流场内分布混合能力;将分散准数与剪切速率相结合,表征了流场的分散混合能力。当两组螺杆单位时间转过的总圈数一致时,螺杆转速比为2∶3的组合混合能力稍优于转速比为2∶1的组合。 相似文献
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陕西某地泥炭腐植酸提取工艺的实验研究 总被引:1,自引:1,他引:0
本实验与陕西某地合作,就当地泥炭进行了分析,并在腐植酸的提取的实验研究中对腐植酸提取的传统工艺做了改进,采取先用NaOH水溶液浸泡泥炭,再在球磨机中进行水磨(同样的仪器干磨粒度只能到60~80目,而水磨可以到100~150目).再絮凝,提取时间缩短到了1 h(传统的方法需要1.5 h)<'[1] >,腐植酸的提取率提高... 相似文献
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针对干清粪式养猪废水 浓度高和低C/N比的特点构建了四格室木质填料床A/O处理系统,通过调控运行探讨其除氮效能和机制。结果表明,在HRT 18.7 h、32℃、硝化液回流比200%、好氧区DO 1.5 mg·L-1等条件下,即便进水 高达307.7 mg·L-1,COD/TN平均为0.47,系统对COD、 和TN的去除率仍能维持在66.5%、93.6%和89.0%左右,TN去除负荷达到0.22 kg·m-3·d-1以上。系统对COD和TN的去除表现出一定的空间分区特征,其中前三厌氧格室是去除COD主要功能区,末端好氧格室是脱氮功能区。系统的脱氮机制以短程硝化反硝化为主,枯木填料的腐解为反硝化提供了必要的碳源。 相似文献
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Catalysis and the oil-based industry (1930-1960) 总被引:1,自引:0,他引:1
M.W. Roberts 《Catalysis Letters》2000,67(1):17-21
One of the most important petroleum refining processes - catalytic cracking - was conceived and developed by Eugene J. Houdry
in France as early as 1929 but it was after he joined Sun Oil in the USA that it was realised commercially in 1937. This was
a period when industrial developments were rapid and with the discovery of rich oil-fields in Saudi Arabia in the 1940s the
gradual dominance of an oil-based rather than a coal based economy was emerging. Progress was particularly rapid in the USA
with contributions from I patieff, Pines, Plank, C.L. Thomas and Haensel. Previously coal hydrogenation had been pioneered
in Germany by Franz Fischer and Hans Tropsch to give long chain hydrocarbons and by Friedrich Bergius to give liquid hydrocarbons.
This revised version was published online in July 2006 with corrections to the Cover Date.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献