超细骨碳除氟效果及影响因素的观察

目的:观察超细骨碳除氟效果及其影响因素。方法:比较三种吸附材料(竹碳、骨碳、活性碳)的超细颗粒对饮水中氟离子的吸附能力,pH值、聚合氯化铝对除氟效果的影响以及在自来水中的除氟效果。结果:骨碳与其他几种吸附材料相比具有较好的除氟效果,骨碳和混凝剂联合除氟效果比骨碳单独除氟效果要好,但达不到两者之和,在自来水中的除氟效果比在蒸馏水中要好且时间短。结论:骨碳超细粉有一定的除氟效果,但达到吸附饱和大约需9 0 min,与实际应用还有一定的距离。     

One‐step radiosynthesis of 4‐[18F]flouro‐3‐nitro‐N‐2‐propyn‐1‐yl‐benzamide ([18F]FNPB): a new stable aromatic porosthetic group for efficient labeling of peptides with fluorine‐18

4‐[¹⁸F]flouro‐3‐nitro‐N‐2‐propyn‐1‐yl‐benzamide ([¹⁸F]FNPB) was developed as a new stable aromatic prosthetic group for more efficient click labeling of peptides. A new aromatic precursor 3,4‐dinitro‐N‐2‐propyn‐1‐yl‐benzamide was radiofluorinated using [¹⁸F]KF/K2.2.2 followed by HPLC purification to obtain the desired product [¹⁸F]FNPB. [¹⁸F]FNPB was synthesized with a 58% radiochemical yield, a specific activity > 350 GBq/µmol, and radiochemical purity was exceeded 98% in 40 min. The in vitro stability studies showed no detectable radiodefluorination over 2 h in mouse plasma. The click labeling yield of three different peptides with [¹⁸F]FNPB were all above 87%. The in vitro study suggests that [¹⁸F]FNPB may be stable in vivo and could have general application in labeling peptides with high radiochemical yield for positron emission tomography applications. Copyright © 2012 John Wiley & Sons, Ltd.     

Management of Solid Waste Containing Fluoride—A Review

Technological and economic development have influenced the amount of post-production waste. Post-industrial waste, generated in the most considerable amount, includes, among others, waste related to the mining, metallurgical, and energy industries. Various non-hazardous or hazardous wastes can be used to produce new construction materials after the “solidification/stabilization” processes. They can be used as admixtures or raw materials. However, the production of construction materials from various non-hazardous or hazardous waste materials is still very limited. In our opinion, special attention should be paid to waste containing fluoride, and the reuse of solid waste containing fluoride is a high priority today. Fluoride is one of the few trace elements that has received much attention due to its harmful effects on the environment and human and animal health. In addition to natural sources, industry, which discharges wastewater containing F− ions into surface waters, also increases fluoride concentration in waters and pollutes the environment. Therefore, developing effective and robust technologies to remove fluoride excess from the aquatic environment is becoming extremely important. This review aims to cover a wide variety of procedures that have been used to remove fluoride from drinking water and industrial wastewater. In addition, the ability to absorb fluoride, among others, by industrial by-products, agricultural waste, and biomass materials were reviewed.     

湿法磷酸制牙膏级磷酸氢钙中的脱氟工艺

针对由中低品位磷矿石制得的湿法磷酸，提出采用预脱氟和灰乳中和深度脱氟相结合的工艺路线，使净化后的湿法磷酸达到作为生产牙膏级磷酸氢钙原料酸的指标要求。实验表明，钾盐的脱氟效果与磷酸的浓度有一定关系，同时活性氧化硅有且于氟的进一步脱除；在进一步的净化过程中，用石灰乳中和至一定的ｐＨ值，绝大部分的氟及其它杂质沉淀析出脱除，净化酸达到了牙膏级磷酸氢钙的生产要求。     

Characterization of the fluoroacetate detoxication enzymes of rat liver cytosol

Two forms of fluoroacetate-specific defluorinase (FSD) were purified from rat hepatic cytosol. The first form, FSD1 (molecular weight 38?kDa), contained 81% of the total cytosolic fluoroacetate defluorination activity and did not bind to the glutathione-affinity, orange A or mono P columns used in the purification procedures. The second form, FSD2 (molecular weight 27?kDa), contained only 13% of the fluoroacetate defluorination activity, had a pI?=?7.8, and exhibited a high glutathione S-transferase (GST)-like activity towards dichloroacetic acid. The FSD1 proteins were identified from peptide mass data and best matched with rat sorbitol dehydrogenase (SDH) (short form), although pure sheep liver SDH enzyme did not possess defluorination activity when subsequently investigated. The FSD2 protein was identified from peptide mass data and best matched with the amino acid sequence of mouse and human Zeta 1 of glutathione S-transferase (GSTZ1) and showed a high GSTZ1 specific activity. This study suggests that the major FSD component (FSD1) represents a new and unique dehalogenating or dehydrogenating enzyme present in rat liver cytosol. The minor FSD component (FSD2) is due to the GSTZ1 present in rat liver cytosol. However, it is not yet clear that FSD1 is indeed SDH and FSD2 is indeed GSTZ1, due to sequence homology being less than 60 and 45%, respectively.     

混配沉淀剂脱除二水湿法磷酸中氟的研究

以四川金河磷矿制得的二水湿法磷酸为对象 ,采用化学沉淀法 ,研究沉淀剂种类、用量 ,加入方式 ,反应温度 ,反应时间 ,液相混合状况以及沉淀剂配制方法对脱除磷酸中氟的影响。将实验数据回归整理得到 :(1)沉淀剂用量与磷酸中剩余氟含量的关系式 ;(2 )磷酸的脱氟温度与磷酸中剩余氟含量的关系式。当磷酸中先加入 Na2 S·9H2 O,后加入 Na2 CO3(分别为脱氟所需理论用量的 10 0 %和 2 0 0 % ) ,在 2 5～ 30℃ ,反应 2 5～ 30 m in,则磷酸中剩余氟、砷和铅等的含量将降至很低     

The role of fluoroacetate-specific dehalogenase and glutathione transferase in the metabolism of fluoroacetamide and 2,4-dinitrofluorobenzene

2,4-Dinitrofluorobenzene (DNFB) reacts with glutathione to form a stable product similar to that formed with the model glutathione-S-transferase (GST) substrate, 1-chloro-2,4-dinitrobenzene (CDNB). DNFB is approx. 40 times als reactive as CDNB in this chemical reaction. The enzymatic defluorination of DNFB also proceeds at a more rapid rate than that of CDNB in the GST assay. Fluoroacetamide (FAM), like fluoroacetate (FAC), undergoes no discernable chemical defluorination. Its enzymatic defluorination is approx. 10% of that observed for FAC and only 0.2% of the rate for DNFB. An antibody raised to the fluoroacetate specific dehalogenase (FSD) precipitated both FAC and FAM defluorinating activity but had no effect on either CDNB or DNFB activity. The data are consistent with the hypothesis that DNFB is metabolized by the GST while FAM is metabolized by the FSD.     

Effective MicroPET imaging of brain 5‐HT1A receptors in rats with [18F]MeFWAY by suppression of radioligand defluorination

Introduction: [¹⁸F]MeFWAY has been developed for imaging the serotonin 1A receptors in the brain. The purpose of this study were to verify the metabolic stability of [¹⁸F]MeFWAY, to measure the degree of defluorination of [¹⁸F]MeFWAY in vivo, to investigate methods of inhibition of defluorination of [¹⁸F]MeFWAY, and to assess the efficacy of [¹⁸F]MeFWAY in rat brains in vivo. Methods: MicroPET experiments in rats were conducted to confirm the distribution of radioactivity in the brain. Nondisplaceable binding potential (BP_ND) in the hippocampus and frontal cortex were also analyzed. Miconazole and fluconazole were tested for the ability to suppress defluorination of [¹⁸F]MeFWAY. We conducted a blockade and displacement experiment by treating with WAY‐100635. Results: In vitro stability tests showed that MeFWAY was very stable in serum for 6 h, but PET revealed that authentic [¹⁸F]MeFWAY underwent significant defluorination in vivo. In vitro inhibition study against decreasing parent activity in liver microsomes, miconazole and fluconazole suppressed metabolic elimination of MeFWAY. However, in the PET study, fluconazole showed more potent inhibitory activity than miconazole. In the suppression of metabolizing enzymes using fluconazole, radioactivity in skull was dramatically decreased by 81% (compared with 69% with miconazole) and it was coupled with an increase in brain uptake. Moreover, BP_ND in hippocampus was 5.53 and 2.66 in frontal cortex. The blockade and displacement study showed the specificity of [¹⁸F]MeFWAY to 5‐HT_1A receptors. Conclusion: In the rat brain, [¹⁸F]MeFWAY microPET showed skull uptake due to defluorination in vivo. We can effectively overcome this drawback with fluconazole. Synapse, 2012. © 2012 Wiley Periodicals, Inc.     

焦化废水脱氟脱色的膜分离机制

针对经Ⅰ级（化学回收法）、Ⅱ级（预反硝化/硝化法，或称A/O工艺）和化学絮凝处理后的不能直接排放的轻污染焦化废水体系，通过研究动态膜及其分离机制，使废水色度≤50（稀释倍数法），氟≤6mg/L，氰≤0.5mg/L,CODcr≤100mg/L，可以达排放或试行总排水循环利用。     

我国改灶降氟防治燃煤型氟中毒效果的评价

目的分析我国燃煤型氟中毒的改灶降氟防治效果及其影响因素,为防治氟中毒提供科学依据。方法计算机检索中文期刊全文数据库、中国生物医学文献数据库、中文科技期刊数据库和中国优秀博士学位论文数据库。检索时间截至2005年12月。同时检索纳入文献的参考文献。居室保温性与改灶降氟防治效果的资料来源于三峡库区监测点。通过制定纳入和排除标准严格筛选相关文献,对研究证据进行质量评价,对燃煤型氟中毒改灶降氟防治效果的相关指标进行相关分析。结果共纳入12篇文献,质量评价结果9篇为C级,3篇为D级。炉灶正常使用下降率与8～12岁氟斑牙、尿氟下降率呈负相关(Pearson相关系数分别为r=–0.87、–0.63,P<0.01、0.05)。氟斑牙下降率和炉灶正常使用下降率与居室保温性能间具相关关系(两个等级相关系数相同,均为r=–1.00,P<0.01)。结论我国改灶降氟防治燃煤型氟中毒效果方面的研究尚缺乏高质量的证据。本研究结果提示对改灶降氟防治燃煤型氟中毒而言,不仅改灶重要,改灶后的正确使用与维护和住房改造提高其保温性也与防治效果有关。