高镁磷尾矿浮选提镁试验研究

以高镁磷尾矿为研究对象,采用一段磨矿正浮选工艺对磷尾矿进行再选试验,考察了磨矿细度,抑制剂、捕收剂、煤油用量对浮选效果的影响。试验结果表明:在磨矿细度为-200目占60.85%,抑制剂硫酸用量为10kg/t、捕收剂TS用量为1200g/t、辅助捕收剂煤油用量为200g/t的条件下,MgO有较好的浮选效果,最终获得品位为21.71%,回收率为78.55%的镁精矿。     

提高煤泥浮选捕收剂性能的试验研究

针对煤泥浮选捕收剂分散难、选择性差、用量大等问题,利用不同化工产品及表面活性剂,将煤油制备成复合捕收剂用于煤泥浮选。分别进行了煤油、复合捕收剂的优选试验及浮选速度试验。优选试验表明:当煤油用量为900 g/t,仲辛醇用量为450 g/t时,煤油浮选效果最佳;当Fy-4复合捕收剂用量为500 g/t,仲辛醇用量为450 g/t时,精煤灰分为9.96%,精煤产率为88.72%,可燃体回收率为94.82%,在精煤灰分相近的条件下,Fy-4复合捕收剂的用量比煤油降低了44.44%,精煤产率和可燃体回收率分别提高了0.06%和0.16%。浮选速度试验表明:Fy-4复合捕收剂不仅节省了药剂用量,而且提高了煤泥浮选活性,提升了精煤浮选速度。最后探讨了无机电解质NaCl对复合捕收剂浮选效果的影响,当NaCl浓度为0.05 mol/L时,煤泥颗粒Zeta电位更趋近零电点,降低了煤泥颗粒的相对接触角,改善了煤泥浮选效果。     

云南某中低品位风化磷矿选矿实验研究

云南某中低品位磷矿,含镁低、硅高,风化程度较深。采用捕收性能强,选择性能高的磷矿正浮选脱硅常温捕收剂HH进行试验研究。结果表明:在采用一粗一扫正浮选闭路工艺流程,在磨矿细度小于74μm粒级质量分数为90%,抑制剂水玻璃用量为9.0 kg/t,捕收剂用量为1.7 kg/t的条件下,可获得磷精矿P_2O_5品位为29.26%,MgO质量分数为0.83%,精矿产率为65.62%,P_2O_5回收率为89.05%的浮选试验指标。     

高硫煤浮选法脱硫实验研究

采用浮选法脱除贵州某煤中的硫,以磺化煤油为捕收剂,WP溶液为起泡剂,CaO为抑制剂,考察了捕收剂用量、起泡剂用量、抑制剂用量以及矿浆浓度对脱硫率的影响。实验结果表明,在捕收剂用量30kg/t、起泡剂用量1.250kg/t、抑制剂用量37.5kg/t、矿浆质量浓度106g/L的条件下,能有效脱除煤中的硫分,脱硫率达到67.63%。对比分析脱硫前后煤样,结果表明浮选法脱除煤中硫的同时,也提高了煤样的热值,提升了煤的质量。     

中低品位胶磷矿常温正反浮选试验

远安磷矿属于中低品位硅钙质胶磷矿,且磨矿后有用矿物与脉石矿物在各粒级中分布较为分散,适宜采用常温正反浮选工艺处理。通过条件试验确定了适宜的工艺参数,即磨矿细度-0.074mm质量分数占87.81%,正浮选碳酸钠用量6.0kg/t,水玻璃用量6.0kg/t,捕收剂RC-10用量0.9kg/t,反浮选硫酸用量15.0kg/t,RC-10用量0.4kg/t。采用常温正浮选1粗1精1扫、反浮选1粗1扫工艺处理P2O5品位21.86%的远安磷矿,可获得最终精矿P2O5品位30.95%、P2O5回收率90.51%、MgO质量分数0.80%的闭路选矿指标,倍半氧化物(Al2O3+Fe2O3)质量分数由原矿的7.50%降低至2.82%,精矿品质得到了较大的提升。浮选产品的各粒级组分质量分数分布结果表明:捕收剂RC-10对0.038mm以上粒级具有较强的浮选性能,进一步提高磷矿资源利用率的关键在于微细粒浮选技术的改进。     

瓮福磷矿a层矿正反浮选工艺研究

以贵州瓮福磷矿a层矿为研究对象,借助XRD、显微镜等对原矿性质进行分析,在此基础上开展了矿石磨矿矿浆质量分数和磨矿细度试验,确定合适的磨矿矿浆质量分数为75%、磨矿细度为-0.075 mm质量分数占80%。利用单因素条件试验和正交试验确定:合适的正浮选捕收剂WF-03用量为1.8 kg/t,调整剂Na_(2)CO_(3)和抑制剂Na_(2)SiO_(3)用量分别为3 kg/t和4 kg/t,矿浆pH为10;合适的反浮选捕收剂WF-01用量为2 kg/t,矿浆pH为4。在试验确定的条件下进行正反浮选开路试验,获得了P_(2)O_(5)品位为31.54%、MgO质量分数为0.86%、SiO_(2)质量分数为10.83%、R_(2)O_(3)质量分数为3.52%、P_(2)O_(5)回收率为80.91%的磷精矿指标。     

用于磷矿浮选的不同聚合度AEO增效棉油酸皂的性能研究

为了探究不同聚合度脂肪醇聚氧乙烯醚(AEO)对棉油酸皂的增效作用,通过单一正浮选流程考察了不同聚合度AEO增效棉油酸皂的最佳配比,并筛选出增效作用最强的AEO-5与棉油酸皂复配成捕收剂用于宜昌磷矿浮选。试验结果表明:AEO对于棉油酸皂浮选有明显增效作用,不同聚合度AEO相比棉油酸皂浮选时磷精矿品位提高1.14%~2.91%,产率提高14.38%~30.15%,回收率提高19.19%~41.79%,选矿效率提高4.81%~11.64%。AEO-5复配比为10%且用量为1.4kg/t时,在所有不同聚合度AEO中其增效作用最强,将按此比例复配棉油酸皂获得的捕收剂ZLX-28用于本试验。在磨矿细度为-0.074mm质量分数占75.5%,粗选碳酸钠用量为7kg/t,水玻璃用量为3kg/t,捕收剂用量为1.24kg/t,扫选捕收剂用量为0.3kg/t,反浮选粗选硫酸用量为12kg/t,磷酸用量为1kg/t,反浮选捕收剂用量为0.52kg/t,扫选硫酸用量为2kg/t的条件下,进行了正浮选1粗1精1扫,反浮选1粗1扫的闭路流程试验,结果能够将磷矿品位从19.97%提高到30.48%,回收率达到89.58%。     

高镁磷尾矿浮选回收镁的研究

以高镁磷尾矿为研究对象,考察了磨矿细度、浮选时间、硫酸用量、脂肪酸与羟肟酸协同用药对浮选效果的影响。"1粗1扫"浮选工艺流程试验的结果表明:在磨矿细度为-74μm质量分数占88.72%,硫酸用量为16kg/t、捕收剂脂肪酸用量为0.93kg/t,羟肟酸用量为0.47kg/t的条件下,MgO浮选效果较好,最终获得了品位为19.05%、回收率为91.19%的镁精矿。     

胶磷矿反浮扫选试验研究

某胶磷矿反浮粗选尾矿P2O5品位为18.99％、MgO质量分数为8.37％,由于反浮粗选尾矿的P2O5品位较高,因此需通过扫选提高最终精矿的产率和P2 O 5回收率.通过试验确定的扫选最佳工艺条件为:浮选矿浆质量分数25.15％、抑制剂用量0 kg/t、调整剂用量3 kg/t、捕收剂用量0.3 kg/t、浮选时间7 m...     

湖北某中低品位胶磷矿反浮选脱镁试验研究

以湖北某中低品位高镁胶磷矿(P₂O₅品位19.37%,MgO质量分数9.90%)为研究对象,采用自制的新型反浮选脱镁捕收剂HLF,在25℃条件下进行单一反浮选试验,结果表明：在磨矿细度为-0.074 mm占70%、磷酸用量为18 kg/t、捕收剂HLF用量为1.6 kg/t的最佳条件下,得到了精矿品位为30.64%、回收率为82.05%、选矿效率为33.17%的良好浮选指标。精矿产品多元素分析和扫描电镜能谱分析结果显示,氟磷灰石与白云石实现了较好的分离。浮选优化试验结果表明,用硫酸替换磷酸作为抑制剂可达到同样的浮选效果,且能降低选矿成本。通过对比HLF和油酸钠单一反浮选脱镁指标,发现HLF相比油酸钠有更为优异的反浮选脱镁性能。研究成果可为中低品位胶磷矿的浮选研究提供借鉴。     

Many Drugs of Abuse May Be Acutely Transformed to Dopamine,Norepinephrine and Epinephrine In Vivo

It is well established that a wide range of drugs of abuse acutely boost the signaling of the sympathetic nervous system and the hypothalamic–pituitary–adrenal (HPA) axis, where norepinephrine and epinephrine are major output molecules. This stimulatory effect is accompanied by such symptoms as elevated heart rate and blood pressure, more rapid breathing, increased body temperature and sweating, and pupillary dilation, as well as the intoxicating or euphoric subjective properties of the drug. While many drugs of abuse are thought to achieve their intoxicating effects by modulating the monoaminergic neurotransmitter systems (i.e., serotonin, norepinephrine, dopamine) by binding to these receptors or otherwise affecting their synaptic signaling, this paper puts forth the hypothesis that many of these drugs are actually acutely converted to catecholamines (dopamine, norepinephrine, epinephrine) in vivo, in addition to transformation to their known metabolites. In this manner, a range of stimulants, opioids, and psychedelics (as well as alcohol) may partially achieve their intoxicating properties, as well as side effects, due to this putative transformation to catecholamines. If this hypothesis is correct, it would alter our understanding of the basic biosynthetic pathways for generating these important signaling molecules, while also modifying our view of the neural substrates underlying substance abuse and dependence, including psychological stress-induced relapse. Importantly, there is a direct way to test the overarching hypothesis: administer (either centrally or peripherally) stable isotope versions of these drugs to model organisms such as rodents (or even to humans) and then use liquid chromatography-mass spectrometry to determine if the labeled drug is converted to labeled catecholamines in brain, blood plasma, or urine samples.     

Insect antifeedant properties of anthranoids from the genusVismia

Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria.     

ICP-MS法测定地球化学样品中As、Cr、Ge、V等18种微量痕量元素的研究

建立了测定地球化学样品中包括As、Cr、Ge、V等18种微量、痕量元素的ICP-MS方法。地化试样用HF-HNO3混酸分解后,以1 1 HNO3溶解干渣。由于制样不使用盐酸,避免了Cl对As、Cr、Ge、V的质谱干扰。用国家一级地球化学标准物质GBW 07309制备溶液优化仪器工作参数,并用于校准。方法测定限(6s)为:0.007~6.4μg/g,精密度(RSD%,n=12)为:29%~9.4%,经过国家一级地球化学标准物质的分析验证,结果与标准值吻合。方法已应用于国土资源调查的试样分析。     

Direct observation of freeze-thaw instability of latex coatings via high pressure freezing and cryogenic SEM

Despite its industrial importance, the subject of freeze-thaw (F/T) stability of latex coatings has not been studied extensively. There is also a lack of fundamental understanding about the process and the mechanisms through which a coating becomes destabilized. High pressure (2100 bar) freezing fixes the state of water-suspended particles of polymer binder and inorganic pigments without the growth of ice crystals during freezing that produce artifacts in direct imaging scanning electron microscopy (SEM) of fracture surfaces of frozen coatings. We show that by incorporating copolymerizable functional monomers, it is possible to achieve F/T stability in polymer latexes and in low-VOC paints, as judged by the microstructures revealed by the cryogenic SEM technique. Particle coalescence as well as pigment segregation in F/T unstable systems are visualized. In order to achieve F/T stability in paints, latex particles must not flocculate and should provide protection to inorganic pigment and extender particles. Because of the unique capabilities of the cryogenic SEM, we are able to separate the effects of freezing and thawing, and study the influence of the rate of freezing and thawing on F/T stability. Destabilization can be caused by either freezing or thawing. A slow freezing process is more detrimental to F/T stability than a fast freezing process; the latter actually preserves suspension stability during freezing. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004 in Chicago, IL. Tied for first place in The John A. Gordon Best Paper Competition.     

Ethanol and (−)-α-Pinene: Attractant Kairomones for Bark and Ambrosia Beetles in the Southeastern US

In 2002–2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae and Platypodidae) to traps baited with ethanol and/or (−)-α-pinene in the southeastern US. Eight field trials were conducted in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures (release rate, about 0.6 g/day at 25–28°C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (−)-α-pinene lures (release rate, 2–6 g/day at 25–28°C) were attractive to five bark beetle species (Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (−)-α-pinene in some locations. (−)-α-Pinene interrupted the response of some ambrosia beetle species to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were exotic and accounted for 70–97% of total catches of ambrosia beetles. Our results provide support for the continued use of separate traps baited with ethanol alone and ethanol with (−)-α-pinene to detect and monitor common bark and ambrosia beetles from the southeastern region of the US.     

基于ATRP法制备的触角状亲水性羟胺树脂的吸硼性能的研究

以大分子引发剂氯乙酰化聚苯乙烯微球(PS-acyl-Cl)经原子转移自由基聚合(ATRP)法引发丙烯酰胺(AM)和甲基丙烯酸缩水甘油酯(GMA)单体的共聚接枝,制得一种触角状亲水性环氧载体(PS-acyl-g-P(AM-co-GMA)),再经二乙醇胺(DEA)的环氧基开环胺化反应,得到一种含多个-NCH2CH2OH螯合配基的多齿-五元螯合环的触角状亲水性羟胺树脂(PS-acyl-g-P(AM-co-GMA)-DEA)。将此树脂用于硼吸附研究,结果表明,PS-acyl-g-P(AM-co-GMA)-DEA树脂对硼的吸附满足Langmuir方程,为单分子层吸附;饱和吸附量约为37.7 mg·g-1,且树脂5 min即可达到吸附平衡,与其它已报道的吸硼树脂相比,该树脂具有更高的吸附量和吸硼速率。吸附动力学研究表明,树脂吸附硼的过程主要由颗粒扩散过程控制。重复使用5次后该树脂的吸附量基本不变,解吸率均在90%以上,重复使用性能良好。