赤泥盐酸浸出液制备聚合氯化铝钙的研究

以赤泥盐酸浸出液、NaOH为原料在一定条件下进行反应聚合、干燥制备无机高分子混凝剂-聚合氯化铝钙的研究。结果显示NaOH的加入量为1 mol,PH值为3,反应温度为60℃,较适宜于产品的合成。     

The development of students' justifications for their positions regarding two theoretical models: Electron cloud or sodium chloride crystal—After engaging in different learning activities

The purpose of this study was to explore high school students' ideas regarding two theoretical scientific models, either electron cloud or sodium chloride crystal, in the context of active learning in small groups. Conversations among peers regarding these models took place during two types of active learning activities: small-group discussion and whole-class debate. The study was conducted in four different high school classes, each of which was in a different school for girls in Oman. The study included 108 grade 10 female students. Two of the classes discussed the electron cloud and the other two classes discussed the sodium chloride model. Qualitative data included students' written responses to prompts, class worksheets, and field notes of student ideas in class debates. In each class, the teacher used a teaching sequence during which the participants expressed their justifications for their positions in writing regarding the particular model on five different occasions, as they progressed through three interactive small group learning activities. The participants' written responses were analyzed using a coding scheme comprising of eight different categories describing the participants' type of justifications regarding the theoretical scientific models: nonsense, approval, mental, experimental, appreciative, external, structural, and modeling. The findings indicated that participants' justifications for their positions regarding theoretical scientific models tended to change over time following each group learning activity. Participants focused their discussion more on external factors, such as the teacher, textbook, religion, and media, after discussions with peers in small groups. In contrast, later their attention focused more on the submicroscopic structural orientations of the model under study during and after engaging in a debating activity. The researchers reasoned that the nature of cognitive demands during each type of active learning activity might play a role in this regard. However, further research to advance the understanding of this phenomenon is needed.     

超声水解法制备超细透明氧化铁黄颜料

利用三价铁盐在超声波条件下水解生成透明氧化铁黄颜料,探讨了超声水解的影响因素,并对产品进行了沉降时间、耐酸、耐碱及耐热性和TEM等表征分析。     

Determination of benzalkonium chloride in viscous ophthalmic drops of azithromycin by high-performance liquid chromatography

A high-performance liquid chromatography (HPLC) system was used in the reversed phase mode for the determination of benzalkonium chloride (BKC) in azithromycin viscous ophthalmic drops. A Venusil-XBP(L)-C_(18) (150 mm×4.6 mm, 5 μm) column was used at 50 ℃. The mobile phase consisted of a mixture of methanol-potassium phosphate (16:5, v/v). Two sample preparation methods were compared. The results suggested that, compared with an extraction procedure, a deproteinization procedure was much quicker and more convenient. Using the deproteinization procedure for sample preparation, calibration curves were linear in the range 5.0～50 μg/ml. The within-day and inter-day coefficients of variation were less than 10%. The average recoveries were determined as 96.70%, 98.52%, and 97.96% at concentrations of 10.0, 30.0, and 50.0 μg/ml, respectively. Variability in precision did not exceed 5%. In conclusion, this HPLC method using a simple sample treatment procedure appears suitable for monitoring BKC content in azithromycin viscous ophthalmic drops.     

利用本地资源制备净水剂的研究

研究了以本地废弃资源铝矾土矿、硫铁矿渣、红土等为原料制备净水剂的方法,并进行了产品净水效果实验.     

Regeneration of Red Cell Cholinesterase Activity Following Pralidoxime (2-PAM) Infusion in First 24 h in Organophosphate Poisoned Patients

Oximes such as pralidoxime chloride reactivate acetylcholinesterase. However their role in management of organophosphate poisoning is controversial. The study was carried out to find effectiveness of pralidoxime chloride (2-PAM) in regenerating red cell acetyl cholinesterase in first 24 h following administration of it in dose recommended by WHO. Eight patients with OPP [chlorpyriphos (3), phorate (3), dichlorvos (1) and monocrotophos (1) who fulfilled the criteria for inclusion were investigated. In addition to decontamination and atropine, all these patients were administered 30 mg/kg body wt of 2-PAM as bolus dose followed by 7.5 mg/kg body wt/h with maximum dose being 500 mg/h as continuous infusion till first 24 h. Red cell AChE activity was estimated every 15 min for first 4 h, one hourly for next 4 h and then 2 hourly till 24 h and subsequently without 2-PAM every 12 h till 7 days or discharge or death which ever earlier. In all the patients maximum increase in activity was observed in first 4 h following which rise was very slow despite continued 2-PAM infusion and reaching a steady state in 20 h in all the cases. The increase in red cell AChE activity observed in diethyl group at 24 h of 2-PAM infusion was 154% vs. 81% in dimethyl group. At 7 days the increase in activity was 215% vs. 118% respectively. However on multiple repeated ANOVA, no statistically significant difference was observed between diethyl and dimethyl groups at admission and discharge (P > 0.05). Similarly no significant difference was observed in three groups when patients were categorized according to WHO classification of organophosphates (P > 0.05). The maximum increase in red cell AChE activity occurs in first 4 h of 2-PAM administration followed by a slow increase despite 2-PAM infusion till 24 h.     

赤铁矿制备聚硅酸铁絮凝剂的性能研究

为利用赤铁矿、工业盐酸及硅酸钠为原料,制备聚硅酸氯化铁絮凝剂的方法并得出最佳条件,运用实验分析、文献分析及比较分析的方法,对聚硅酸氯化铁混凝性能进行了相关分析,并对聚硅酸氯化铁絮凝剂的性能进行了简要分析。结果表明,酸浸的温度、反应的时间、盐酸的浓度以及液固比均对铁的浸出有一定的影响,得到的最佳条件使铁的浸出率可达到94.58%;该方法制备的聚硅酸氯化铁絮凝剂pH适用范围较广,在整个中性和弱碱性范围内的处理效果较好;处理水的温度在10～30℃时,其效果较好;与市售的絮凝剂比较,在加药量相同的情况下,具有形成絮体速度较快,沉降速度快的优点。     

Hypertonic saline resuscitation maintains a more balanced profile of T-lymphocyte subpopulations in a rat model of hemorrhagic shock

Objective： To investigate the potential and early effect of hypertonic saline resuscitation on T-lymphocyte subpopulations in rats with hemorrhagic shock. Methods： A model of rat with severe hemorrhagic shock was established in 18 Sprague-Dawley （SD） rats. The rats were randomly divided into Sham group, HTS group （hypertonic saline resuscitation group） and NS group （normal saline resuscitation group）. Each group contained 6 rats. The CD4~ and CD8~ subpopulations of T-lymphocytes in peripheral blood were detected respectively before shock and after resuscitation by double antibody labelling and flow cytometry. Results： In the early stage after hemorrhagic shock, fluid resuscitation and emergency treatment, the CD4^＋ lymphocytes of peripheral blood in HTS and NS groups markedly increased. Small volume resuscitation with HTS also induced peripheral CD8^＋ lymphocytes to a certain extent, whereas NS resuscitation showed no effect in this respect. Consequently, compared with Sham and HTS groups, CD4^＋/CD8^＋ ratio of peripheral blood in NS group was obviously increased, and showed statistically differences. Conclusion： In this model of rat with severe hemorrhagic shock, small volume resuscitation with HTS is more effective than NS in reducing immunologic disorders and promoting a more balanced profile of T-lymphocyte subpopulations regulating network.     

ISOPROPYLIDENATION OF MONOSACCHARIDES CATALYZED BY SOLID PHASE TiCl_4

ＩＳＯＰＲＯＰＹＬＩＤＥＮＡＴＩＯＮＯＦＭＯＮＯＳＡＣＣＨＡＲＩＤＥＳＣＡＴＡＬＹＺＥＤＢＹＳＯＬＩＤＰＨＡＳＥＴｉＣｌ＿４ＩＳＯＰＲＯＰＹＬＩＤＥＮＡＴＩＯＮＯＦＭＯＮＯＳＡＣＣＨＡＲＩＤＥＳＣＡＴＡＬＹＺＥＤＢＹＳＯＬＩＤＰＨＡＳＥＴｉＣｌ＿４￥...     

微波辐射相转移催化合成对甲苯基苄基醚

以水-95%乙醇为溶剂,以氯化苄和对甲苯酚为原料,在相转移催化作用下,利用微波辐射合成对甲苯基苄基醚。实验表明,对甲苯酚、氯化苄、氢氧化钠的摩尔比为1：1.1：1.1,400W下微波辐射反应6min。对甲苯基苄基醚的产率为96.21%。