重铬酸钾滴定法测定金属化球团中氧化亚铁含量

确定了试样以盐酸分解,重铬酸钾滴定法测定金属铁和亚铁合量,再减去金属铁含量,通过换算得到氧化亚铁含量。通过对不同条件下的试验优化,建立了重铬酸钾滴定法测定金属化球团中氧化亚铁含量试验方法,其测定结果的相对标准偏差为0.41%~0.94%,回收率大于96.0%。     

An Engineered sgsh Mutant Zebrafish Recapitulates Molecular and Behavioural Pathobiology of Sanfilippo Syndrome A/MPS IIIA

Mucopolysaccharidosis IIIA (MPS IIIA, Sanfilippo syndrome type A), a paediatric neurological lysosomal storage disease, is caused by impaired function of the enzyme N-sulfoglucosamine sulfohydrolase (SGSH) resulting in impaired catabolism of heparan sulfate glycosaminoglycan (HS GAG) and its accumulation in tissues. MPS IIIA represents a significant proportion of childhood dementias. This condition generally leads to patient death in the teenage years, yet no effective therapy exists for MPS IIIA and a complete understanding of the mechanisms of MPS IIIA pathogenesis is lacking. Here, we employ targeted CRISPR/Cas9 mutagenesis to generate a model of MPS IIIA in the zebrafish, a model organism with strong genetic tractability and amenity for high-throughput screening. The sgsh^Δex5−6 zebrafish mutant exhibits a complete absence of Sgsh enzymatic activity, leading to progressive accumulation of HS degradation products with age. sgsh^Δex5−6 zebrafish faithfully recapitulate diverse CNS-specific features of MPS IIIA, including neuronal lysosomal overabundance, complex behavioural phenotypes, and profound, lifelong neuroinflammation. We further demonstrate that neuroinflammation in sgsh^Δex5−6 zebrafish is largely dependent on interleukin-1β and can be attenuated via the pharmacological inhibition of Caspase-1, which partially rescues behavioural abnormalities in sgsh^Δex5−6 mutant larvae in a context-dependent manner. We expect the sgsh^Δex5−6 zebrafish mutant to be a valuable resource in gaining a better understanding of MPS IIIA pathobiology towards the development of timely and effective therapeutic interventions.     

磷石膏提质降杂实验研究

磷石膏的综合利用对保护环境、促进企业可持续健康发展具有重要意义,但是磷石膏中的磷、氟、二氧化硅等杂质影响其利用。针对云南磷石膏中二氧化硅含量高的问题,采用正浮选工艺开展了磷石膏提质降杂的实验研究。通过单因素条件实验获得了合适的工艺参数：浮选温度为15 ℃、矿浆pH为2、十二胺用量为300 g/t。在此条件下,进行了“一粗二精”的正浮选开路流程实验,获得了二水石膏（CaSO₄·2H₂O）质量分数为97.5%、二氧化硅质量分数为1.17%的精矿,所得精矿达到了GB/T 23456—2018《磷石膏》一级品指标的要求;二水石膏回收率为98.58%、二氧化硅去除率为92.23%。通过正浮选不仅成功实现了二水石膏和二氧化硅的有效分离,而且磷石膏中的水溶磷和水溶氟也得到了有效去除,从而提高了磷石膏的品质。     

氟硅酸钾滴定法测定粗制氟化钠中二氧化硅

采用硝酸-氢氟酸混合酸为消解溶剂,通过微波消解技术对粗制氟化钠进行快速消解,并用氟硅酸钾滴定法测定其二氧化硅含量。选择饱和氯化钾溶液替代固体氯化钾作为沉淀剂,考察了消解酸体系、饱和氯化钾溶液用量、沉淀温度、沉淀放置时间、共存元素干扰及指示剂选择等条件对测定结果的影响并进行优化。确定了最优测试条件：以8 mL硝酸+2 mL氢氟酸为消解溶剂,以8 mL饱和氯化钾溶液为沉淀剂,控制沉淀温度为20~25 ℃、沉淀放置时间为15 min,选择50 g/L氯化钾-50%乙醇溶液洗涤沉淀,采用溴麝香草酚蓝-酚红指示剂。该方法应用于回收粗制氟化钠中二氧化硅含量的测定可大幅度缩短分解试样的时间,有效降低检测成本,回收率为99.15%~100.63%,相对标准偏差（RSD,n=8）小于1%,与传统高温碱熔法测定结果相符,方法的准确度和精密度较好。     

高温熔融-电感耦合等离子体原子发射光谱法测定含铁尘泥中5种有害元素

准确、快速地测定含铁尘泥中有害元素,对含铁尘泥节能降废项目研究及综合利用有着重要的指导意义。实验针对含铁尘泥试样因含碳量高,导致常规酸溶解方法如果不增加除碳步骤则很难完全分解试样的问题,采用高温熔融法将试样制成熔融液后倾倒于稀酸中溶解的方法,解决了碳含量高难溶解的问题。采用四硼酸锂-碳酸锂混合熔剂在高温下将试样熔融,熔融液高温倾倒于稀酸中制成澄清溶液,由于骤冷,试样炸裂成微小玻璃珠,无迸溅,操作简单,使得后续溶解过程快速完成,从而建立了电感耦合等离子体原子发射光谱(ICP-AES)测定P、Pb、K、Na、Zn共5种有害元素的方法。按照实验方法测定含铁尘泥中P、Pb、K、Na、Zn,测定值的相对标准偏差(RSD,n=9)在1.4%～5.7%之间,加标回收率在96%～110%之间。研究结果表明方法能够满足含铁尘泥样品中5种元素的定量分析要求。     

C型钢成型机的自动控制系统

本文介绍了液压数控冲剪式C型钢成型机的PLC控制系统的设计、实现及应用，该系统工作可靠，使用方便，极大地提高了C型钢成型机的自动化程度及生产效率。     

镀锌钢管双引出工艺设备的探讨

分析了我国镀锌钢管双引出工艺设备的现状。介绍了星轮齿盘式与螺旋式双引出工艺设备的特点，指出双排螺旋机组的综合指标较高，并对齿盘式双引出机组的磁力辊道及镀后处理设备提出了改进设想。     

季胺萃取锌的动力学研究

以恒界面池法研究了氯化物介质中季胺萃锌的动力学。考查了搅拌转速、传质界面积和温度对萃取速率的影响，判定季爱萃锌为界面化学反应的动力学模式。进一步研究了季胺萃取剂浓度和水相Ｚｎ＾２＋浓度对萃取速率的影响，得到了与理论推断相吻合的速率方程。     

Initial stages of tin electrodeposition from sulfate baths in the presence of gluconate

Tin electrodeposition in its initial stages in acid sulfate/gluconate baths was studied with varying tin and gluconate concentrations using potential-controlled electrochemical techniques. The deposit morphology was observed by scanning electron microscopy (SEM). A comparison with tin electrodeposition from acid sulfate baths in the absence of gluconate was also carried out. Use of a highly acidic bath leads to nonuniform deposits, even in the presence of gluconate; at pH 4 deposits are uniform, brilliant and suitable for finishing applications. Tin crystallites have a well defined morphology which depends on bath agitation conditions. In the absence of agitation, the crystallites have the same tetragonal shape as in a sulfate bath without gluconate.     

关于生产精制元明粉的探讨

介绍了以山西运城南风自产芒硝为原料生产精制元明粉的几种工艺,以及国内外精制元明粉的市场及生产状况.精制工艺包括化学除杂法、原料优选法、重结晶法.结果表明,精制元明粉的生产过程实质是一个除杂、提纯过程：对于钙离子含量高的原料,可采用化学除杂法;对于氯离子含量高的原料,可采用氯离子富集法、冷冻法或洗涤法;镁离子较难去除,可采用水硝洗涤、冷冻法.