离子交换法净化除杂制取磷酸探索性试验

介绍了在强酸性阳离子交换树脂柱床中，将处理成磷酸二氢盐的溶液通过树脂柱使其中的钙、镁、钡等杂质被吸附在树脂上而与磷酸分离。从而可较简便得到含量达85％的化学纯磷酸。     

蔗糖糖蜜发酵生产L-苹果酸的研究

[目的]研究蔗糖糖蜜预处理、供氧、温度与N源对生产L-苹果酸的影响.[方法]以黄曲霉AF05为出发菌株,蔗糖糖蜜为主要生产原料,通过摇床培养考察糖蜜生产L-苹果酸的发酵条件.[结果]糖蜜预处理能减少糖蜜中有害物质对黄曲霉AF05生长的抑制作用并能促进L-苹果酸的合成,预处理后L-苹果酸含量提高了1倍;当500 ml三角瓶装培养液70～100 ml及摇床转速200～250 r/min时,可获得L-苹果酸合成所需的适合溶氧水平;黄曲霉AF05合成L-苹果酸的最适温度为35 ℃,另外糖蜜培养基需添加1.0 g/L 硫酸铵为N源.[结论] 糖蜜经预处理后,能稳定合成L-苹果酸.     

蔗糖还原浸出锰阳极泥中锰的研究

采用蔗糖还原浸出阳极泥中的锰,通过正交实验和单因素实验,探讨了搅拌速率、液固比、反应温度、反应时间、硫酸浓度、蔗糖浓度等因素对阳极泥锰浸出率的影响,正交实验表明,各因素影响锰浸出率的大小顺序为:硫酸浓度蔗糖浓度浸出温度浸出时间。较优的工艺条件为:硫酸浓度3.5 mol/L,蔗糖浓度70 g/L,液固比为4∶1,搅拌速率100 r/min,反应温度70℃,反应时间40 min,锰浸出率达到98%。     

强酸阳离子交换纤维柱分离-石墨炉原子吸收光谱法测定金属铟及其盐中镉

研究表明,当In的共存量大于或等于400倍Cd量时,石墨炉原子吸收光谱(GFAAS)法直接测定Cd的误差≥+5%。采用强酸阳离子交换纤维柱,控制试液流速为0.6 mL/min进行交换,用相同流速的1.2 mol/L HNO3淋洗交换柱,Cd从纤维柱上首先被洗脱而使之与In达到分离,有效地消除了In对Cd的测定干扰。In与Cd质量比(mIn∶mCd)在100∶1~1 000 000∶1之间,经过纤维柱分离,GFAAS测定Cd的检出限(3S)为1.5×10-5μg/mL,线性范围为5.0×10-5~1.0×10-2μg/mL;加标回收率为98%~102%,RSD(n=6)为0.8%~1.5%。测定金属铟和硫酸铟中Cd的含量分别为17.6μg/g和1.86μg/g,加标平均回收率分别为100%和99%,RSD(n=6)分别为2.0%和2.3%。     

制备高纯氧化钼

制备高纯氧化钼的方法为:(1)将钼酸铵水溶液在pH值为6.0-9.0下与碱性阴离子交换树脂接触以除去杂质W;(2)将形成的水溶液与无机酸混合以结晶出H_2MoO_4;(3)焙烧H_2MoO_4以获得MoO_3;(4)将MoO_3溶解于碱水溶液中,钼与碱的克分子比为1:1,添加H_2O_2溶液,与强酸性阳离子交换树脂接触以分离阳离子;(5)将铵盐     

苗期夜间低温处理对番茄叶片蔗糖代谢的影响

[目的]探讨夜间低温处理对番茄叶片蔗糖代谢的影响.[方法]以夜温15℃为对照,设夜温6℃(18:00～6:00)为处理,处理7d后测定番茄叶片糖和淀粉含量及蔗糖代谢相关酶活性:[结果]夜间低温处理增加了叶片中的果糖、葡萄糖、蔗糖、总糖和淀粉的含量,果糖和葡萄糖含量与对照相比差异不显著,蔗糖、总糖和淀粉含量与对照相比差异达极显著水平;夜间低温处理增加了叶片中酸性转化酶(AI)和中性转化酶(NI)活性,降低了蔗糖合成酶(SS)和蔗糖磷酸合成酶(SPS)活性.[结论]夜间低温导致番茄叶片中光合产物积累,对光合作用产生反馈抑制.     

米邦塔仙人掌提汁新工艺的研究

[目的]探讨一种可食用米邦塔仙人掌汁液提取的新工艺.[方法I利用渗透压胀破细胞壁使汁液流出原理,通过单因素试验和正交试验优化了米邦塔仙人掌汁液提取的工艺条件.[结果]米邦塔仙人掌汁液提取的最优工艺条件:仙人掌与蔗糖的比例为4:1(V:V),提汁时间为12 h,切片厚度为4 mm.在该条件下,仙人掌原汁得率可达84.90%.[结论]为研究米邦塔仙人掌的加工生产提供了理论依据.     

离子交换-超声波联合生产纳米级纯三氧化钼工艺初探

本文以钼酸铵酸洗废水回收钼后的解析液——钼酸钠溶液(含钼10~50 g/L)为原料,采用阳离子交换得到钼酸溶液,通过超声波对钼酸溶液进行处理得到纳米级纯三氧化钼,过程工艺参数对纳米级纯三氧化钼的纯度、粒度、晶形等有重要影响。     

一种铜电解液净化的工艺方法

本发明涉及铜电解液的净化方法,其工艺是将待净化的含有50～250 g/L硫酸的铜电液与螯合性阳离子交换树脂接触,吸附锑、铋后,用含有1～10 g/L碱金属氢氧化物2～60g/L的EDTA水溶液为解析液,洗脱除去树脂上的锑、铋。本工艺不产生酸雾、     

微色谱柱分离分光光度法连续测定包头稀土精矿中铈组稀土和钍

通过阳离子交换树脂微色谱柱分离,建立了分光光度法连续测定稀土精矿中铈组稀土和钍的方法。含大量稀土元素和钍的1 mol/L HCl试液流经HD-8阳离子交换树脂微色谱柱,钍和稀土同时被保留在树脂上,用1 mol/L HCl淋洗杂质元素,4 mol/L HCl-2 mol/LNH4Cl洗脱液洗脱稀土,然后柱子用200 g/L NH4Cl溶液转型,水洗去多余的铵根离子,40g/L草酸铵溶液洗脱保留在柱子上的钍。从柱子洗脱下来的稀土和钍以偶氮胂Ⅲ作显色剂光度法分别测定。该法用于测定包头稀土精矿中铈组稀土和钍,相对标准偏差(RSD)分别为0.24%和2.7%。     

论从实践理解世界的物质性和自然世界的先在性

马克思主义唯物论是一种物本主义形态的唯物论,还是一种超越物本主义形态、从实践理解世界的本质相关问题的实践的唯物主义的唯物论?这是一个我们必须搞清楚的有关马克思主义唯物论的本质规定性和精神实质的重大问题.在考察物本主义的唯物论及其思维方式的局限性的基础上,揭示了马克思主义唯物论是现代的、实践的唯物主义,并重点研讨了马克思主义唯物论关于从实践理解世界的物质性和自然世界的先在性的原理,以期为马克思主义唯物论进一步阐明人类世界的实践性原理奠定基础.     

Effect of cyproheptadine on the ultrastructure of the neurons of the arcuate nucleus in the hypothalamus of the rat

The data are presented on changes in the rat arcuate nuclear neuron ultrastructure after using cyproheptadine (peritol, Egyt Pharmaceutical Works, Hungary) in a water suspension at a dose of 20 mg/kg once daily during 7 successive days and twice a day within 10 days. It was shown that cyproheptadine decreases the functional activity of the arcuate nuclear neurons, depending on the total amount of the drug used. Cyproheptadine-induced inhibition of the forming neurohormone release from neurons is likely to be one of the mechanisms of its therapeutic effect in Itsenko-Cushing's disease.     

Characteristics of the sympathetic innervation of the nictitating membrane and of the vasculature of the nose and tongue of the cat

Vasomotor responses from the nasal mucosa and tongue, and contractions of the nictitating membrane, were recorded on stimulation of the cervical sympathetic or internal carotid nerves. Preganglionic sympathetic nerve fibres which elicited a membrane response possessed a lower threshold than those which evoked nasal vasoconstriction, while the latter displayed a lower threshold than fibres which evoked tongue vasoconstriction. The sympathetic vasodilator fibres to the tongue whose activity was revealed after alpha-receptor blockade, had a similar threshold to the vasoconstrictor fibres. Membrane contraction, nasal vasoconstriction and occasionally tongue vasoconstriction could be evoked by stimulating the internal carotid nerve. The postganglionic fibres innervating the nasal mucosa had a similar threshold to those of the nictitating membrane, which may indicate that there are small myelinated fibres innervating the mucosa. The preganglionic compound nerve action potential had four major components, S1-S4. S1, S2 and usually S3 fibres were associated with membrane contraction; S2, S3 and sometimes S1 fibres were associated with nasal vasoconstriction; and S3, usually S2 and occasionally S1 fibres were associated with vasoconstriction in the tongue. It is concluded that each of these three groups of nerve fibres, but not S4 fibres, may include fibres associated functionally with the three effectors. There was a considerable difference between the relative amplitude of the responses of the three effectors elicited by stimulation of the cervical sympathetic nerve at frequencies between 0.2 and 2 Hz. Vasoconstrictor responses were relatively larger than membrane contractions suggesting differences in the mechanisms of neurotransmission at the neuroeffector junctions.     

Structure of the attachment of the vocal ligament to the perichondrium of the thyroid cartilage

The ventral attachement of the ligamentum vocale of eleven larynges (new-born and adults has been studied in sagittal, frontal and horizontal sections. 1. Supplementary to the known structure of the ventral attachement of the ligamentum vocale we have noticed collagen fibers which ascend in the inner angle of the thyroid cartilage and which partly cross to the other side. Sometimes a few fibers which are running downward have been observed. This structure of the attachement must be more firm than the known structure. 2. Moreover it has been observed that a lot of the angles of the crossing collagen fibers in the cartilage of the lamina mediana (near the attachement of the ligamentum vocale) are right-angled, whereas the angles of the fibers which lie in the laminae laterales in their majority are acute-angled. This phenomenon also is interpreted as a structure which makes the lamina mediana firmer. The fact, that this structure is not so evident in the specimens of the new-born as in those of the adults indicates that there are postnatal changes in the structure of the lamina mediana.