峰峰矿区南环洗煤厂扩场地控制爆破技术

根据爆破环境等实际情况,介绍了某工程爆破方案的选取及设计.采用松动控制爆破技术,控制一次爆破孔数及装药量,选择合理的爆破参数,有效地控制爆破飞石和爆破振动.既保证了爆破施工的安全,又取得良好的经济效益.     

精细爆破在矿山的实践与应用

为提高矿山开采时的爆破效果和爆破质量,将精细爆破的理念融入到常规传统爆破中,优化了台阶深孔爆破设计方案和相关的爆破参数,并结合实际工作经验,对爆破施工工艺、爆破安全管理中的一些细节问题进行了研究和总结,为矿山开采施工作业提供了参考。     

焦山石灰岩矿降低爆破震动效应的技术措施

通过对焦山矿爆破震动的监测分析,总结了影响爆破震动的主要因素。在此基础上,总结介绍了在露天矿爆破设计和施工时,降低爆破震动效应的几种技术措施。如采用微差爆破技术,限制微差爆破最大一段炸药量,选择松动爆破和加强松动爆破,合理确定最小抵抗线方向,等。     

大直径深孔微差爆破时间的选取及应用

微差爆破时间的合理选取是微差爆破技术的关键,结合大塘矿实际,通过理论计算得出了适宜大塘矿的大直径深孔微差爆破时间,为验证爆破时间选取的合理性,开展了爆破试验,结果表明:合理的微差爆破时间有利于降低爆破振动速度,减少爆破振动对地表构建物和井下工程的破坏。爆破炸药单耗从0.2kg/t降低到0.177kg/t,经济效益显著。     

密封膜对正拱开缝型爆破片爆破压力的影响

以多层式爆破片爆破压力计算原理和普通正拱型爆破片爆破压力计算公式为基础 ,推算出正拱开缝型爆破片爆破时密封膜所占爆破压力的比例 ,从而为确定正拱开缝型爆破片强度膜的材料厚度和开缝尺寸提供了重要依据。     

爆炸片爆破压力设计及校核方法探讨

基于GB 567-2012和GB 150-2011标准,对爆破片爆破压力设计和校核流程进行了阐释。详细分析了容器工作压力及设计压力、标定爆破压力、设计爆破压力、最大最小爆破压力之间的关系。结果表明,设计爆破压力是最小爆破压力、爆破压力负允差与制造范围下限绝对值之和。最大爆破压力是设计爆破压力、制造范围上限与爆破压力正允差之和。最小爆破压力与容器工作压力有关,最大爆破压力与容器设计压力有关。最后给出了爆破片爆破压力设计及校核案例。     

浅析降低露天矿台阶爆破大块率的途径

结合云浮硫铁矿台阶爆破生产实践,从影响爆破作用的爆破参数和爆破材料等因素出发,介绍了降低台阶爆破大块率的几种途径。     

硬岩巷道快速掘进技术研究

以某矿十八采区3上辅运巷(东段)为研究对象,分析了多向聚能爆破技术在硬岩巷道掘进中的爆破原理以及其爆破装置的形式,比较了多向聚能爆破技术相较一般爆破技术的优势。并在该掘进工作面采用聚能爆破技术掘进,依据设定的爆破参数爆破,并爆破后对巷道及时进行支护,并对爆破效果进行检验,结果表明聚能爆破提高了进尺和巷道断面精度,对矿井的经济效益也有提高。     

正拱开缝型爆破片爆破性能有限元分析

采用有限元模拟方法,对正拱开缝型爆破片爆破压力进行了研究,探讨了爆破压力与预拱高度、孔间桥长之间的关系。正拱开缝爆破片爆破压力与相对预拱高度成线性关系。正拱开缝型爆破片的承载能力主要由桥长来决定。爆破压力跟桥长在数量上成正比。     

光面护壁爆破在清平磷矿开拓巷道中的应用

介绍了护壁爆破原理和方法,并在清平磷矿开拓巷道和穿脉巷道试用,比较了护壁爆破与常规爆破的爆破效果.     

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。