陶粒压裂支撑剂发展现状及未来展望

随着水力压裂技术的快速发展,陶粒压裂支撑剂研制到现在,在生产上已经规范化。目前市场上有各种规格的陶粒支撑剂,满足不同油气井的开采需要。油气井深度的增加导致开采环境更加复杂,因此,研制性能更好、适合特殊环境的陶粒压裂支撑剂迫在眉睫。文章介绍了陶粒支撑剂的背景及现状,总结了目前陶粒压裂支撑剂制备工艺和存在的问题,重点分析了制备陶粒的影响因素,简要介绍几种新型陶粒压裂支撑剂,最后探讨了陶粒压裂支撑剂发展前景及方向。     

焙烧陶粒膨胀剂的研究应用进展

陶粒因为具有多种优良品质而应用广泛.为获得适合的密度、孔隙度、比表面积和吸水率等性能,焙烧陶粒在制备过程中需要添加膨胀剂.在简述焙烧陶粒膨胀机理的基础上,介绍了焙烧陶粒膨胀剂的种类和特征,并着重介绍了有机碳类膨胀剂、铁氧化物类膨胀剂、碳酸盐类膨胀剂和碳化硅膨胀剂的膨胀特性及相关研究应用情况,分析了铁氧化物和碳质相互作用对陶粒膨胀性能的影响;此外,指出可以根据陶粒的软化温度和膨胀剂的TG-DSC/DTA曲线变化特征合理选择膨胀剂,指出陶粒的制备工艺与设备对其膨胀特性也具有显著影响,为提高焙烧陶粒的制备和应用水平提供参考.     

水处理用陶粒滤料的研究现状

随着曝气生物滤池的发展,对其核心部分—陶粒滤料的研究越来越多。本文从陶粒滤料的特性、制备机理、工艺、原料等方面综述了水处理用陶粒滤料的研究现状,重点介绍了以粉煤灰、污泥和尾矿等固体废弃物为主要原料的新型环保陶粒滤料以及低能耗的免烧陶粒滤料,总结了传统陶粒滤料和新型节能环保陶粒滤料的特点、存在的问题及发展方向。     

正交设计与回归分析在底泥陶粒松散容重研究中的应用

运用L9(34)正交试验设计的方法,研究了底泥陶粒配比中生活污泥、粘结剂、烧成温度等因素,对陶粒松散容重的影响,确定了底泥陶粒的最优配合比为A1B2C3,即:生活污泥含量为5%,粘结剂含量为4%,焙烧温度为1120℃.并利用一元线性回归分析,建立底泥陶粒的松散容重与生活污泥以及烧成温度的线性关系.     

城市污泥陶粒制备技术与应用研究进展

城市污泥是污水处理的副产物,其产生量随着污水处理量及处理率的增大而增大。但是,目前污泥处理处置的规模及水平难以与污水处理水平相匹配。污泥处理主要以无害化为主,资源化利用程度不足。对比了城市污泥与陶粒原料的成分,对城市污泥制备陶粒进行了可行性分析;介绍和分析了制备城市污泥陶粒的基本流程及条件,对城市污泥制陶粒的研究现状和应用进行了相关讨论;对改性陶粒的研究进行了综合评述和展望。结果表明:由于污泥含有大量的有机物,同时含有硅、铝等无机成分,各成分比例适宜,则可在高温下将其制备成陶粒,作为轻质骨料、栽培基质或水处理滤料等进行后续利用;由于污泥陶粒具有一定的吸附能力,可对陶粒进行改性,从而强化其吸附性能;从原料配置、制备条件和功能改性3个方面对污泥陶粒的强度及其对特定污染物的吸附进行有针对性的优化,是污泥陶粒未来的研究方向。     

粉煤灰陶粒的制备技术及研究进展

粉煤灰是中国最大的固废污染源,对其进行高值化应用不仅能变废为宝,而且是中国经济建设中一项重要的技术经济政策,是解决中国电力生产环境污染和资源缺乏之间矛盾的重要手段。粉煤灰陶粒的制备对于粉煤灰资源化利用具有重要意义。综述了粉煤灰陶粒的制备方法及国内外研究进展,分别对焙烧法和免烧法制备粉煤灰陶粒的工艺及机理进行了详细的分析,介绍了粉煤灰陶粒目前的市场应用领域及采用的标准,同时提出了在综合利用过程中存在的问题和解决办法,并对未来的发展趋势进行了展望。     

煤泥制备陶粒滤料的研究

研究了煤泥烧制陶粒滤料的制备工艺,分析了制备过程中预热温度、预热时间、焙烧温度、焙烧时间对陶粒性能的影响,并对煤泥陶粒的膨胀机理进行了探讨。研究结果表明,在最佳工艺条件下制备的陶粒比表面积35.337 m2/g,堆积密度586kg/m3,吸水率48.89%,容重1 023.45 kg/m3,空隙率56%,盐酸可溶率0.54%。     

硼泥陶粒制备工艺的优化实验研究

本文根据硼泥的化学成分设计了制备硼泥陶粒的原料比例,参考相关资料制定了陶粒的预热温度、烧结温度、烧结时间等制备工艺参数,进行基础实验.通过基础实验确定烧制硼泥陶粒的主要影响因素及适宜的工艺参数,进行正交试验,确定制备硼泥陶粒的合理原料配比和最佳的焙烧制度:预热温度450℃,焙烧温度1200℃,焙烧时间15 min.制备出硼泥陶粒试样的技术性能为:表观密度833 kg/m3,筒压强度4.7 MPa,1h吸水率2.3％,远低于吸水率≤22％的国家标准规定,既具有高强膨胀的特性,又具有极低的吸水率.     

我国工业固废制备陶粒资源化利用的研究进展

部分工业固废是极佳的陶粒基体材料,资源化利用工业固废制备陶粒产品可规模化消纳工业固废,同时形成良好的社会环境效益和客观的经济效益.通过文献调研,本文介绍了近几年我国工业固废产生和处理的总体情况,阐述了利用工业固体废弃物制备陶粒的可行性,从所涉及的主要原理以及工艺技术总结了工业固废制备陶粒的理论基础,分析了工业固废制备陶粒的资源化利用和研究现状,表明了目前存在的主要问题并做出合理展望.     

脱硫灰及含油污泥制备陶粒研究

为解决新疆地区脱硫灰和油田油泥处置问题,采用脱硫灰和含油污泥制备陶粒,研究不同配方及烧结工艺对陶粒吸水性能的影响,结合XRD图像对陶粒的晶体结构进行分析,进而解释了影响陶粒吸水性能的主要原因。采用重金属挥发率和浸出率对陶粒制备和利用过程的重金属迁移风险进行量化评估。在陶粒烧制过程中Pb的挥发率是最高的,为62.2%,而陶粒中Cu的重金属浸出率最高,达到了78.4%。     

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.     

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.     

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。