水力旋流器提纯含滑石低品位菱镁矿实验研究

通过光薄片鉴定、XRD和化学分析等方法,对某低品位菱镁矿进行了矿石性质分析研究,确定了该矿石属于含有滑石和绿泥石的高硅高钙型低品位菱镁矿.针对该菱镁矿的性质,采用旋流器预先富集提纯.通过试验确定了旋流器底流口直径、矿浆浓度和给矿压力.在该工艺参数条件下进行试验,对得到的旋流器底流和溢流产品进行分析,底流产率为68.72％,MgO回收率为78.05％,MgO含量为41.33％,较原矿MgO含量提高了4.94％;溢流中滑石和绿泥石得到富集.为后续制备高品质菱镁矿和滑石、绿泥石提供实验依据.     

低品位菱镁矿水化试验研究

针对目前我国低品位菱镁矿利用率低下的现状,提出了对低品位菱镁矿进行开发利用的设想,以辽宁海城低品位菱镁矿为研究对象,对其进行了水化试验研究.通过检测水化过程中低品位菱镁矿中Mg2的水化率及其反应过程中镁元素物相变化这两个指标,分别对低品位菱镁矿水化过程的影响因素进行了试验研究.研究结果表明,在低品位菱镁矿粒度-0.074 mm、反应物料固液比1∶49、反应温度80℃、反应时间50 min的条件下,低品位菱镁矿的水化率高达92.0％,该研究结果为后续低品位菱镁矿的提纯提供试验依据.     

提高菱镁矿浮选回收率试验研究

菱镁矿是我国重要的矿产资源,近年来浮选法选别菱镁矿发展较快,但是目前浮选法提纯菱镁矿时矿物回收率普遍偏低。在磨矿细度-0.074mm质量分数为70.1%,pH值为5.5,六偏磷酸钠用量为150g/t,水玻璃用量为500g/t的条件下,改进常规浮选流程,采用1粗2精反浮选、第2次精选尾矿再选的选矿工艺流程,对辽宁海城某原矿MgO(IL=0)品位为92.32%的菱镁矿进行浮选试验研究,获得MgO(IL=0)品位为96.56%、回收率为83.10%的选别指标,和1粗2精浮选流程相比,在精矿质量相近的情况下,回收率提高6.55%。该浮选工艺简单、易行,可有效提高菱镁矿资源利用率,减少尾矿排放量。     

新疆某地难处理氧化铜矿选矿试验

新疆某铜矿矿石属于凝灰岩型氧化铜矿石,选矿厂采用硫化浮选工艺,存在回收率低、捕收剂耗量高、泡沫量大且发黏等问题。本文主要针对新疆滴水铜矿火山凝灰岩型氧化铜矿样进行了选矿试验研究,试验结果表明:采用混合捕收剂,经过一次粗选,三次扫选和三次精选的浮选流程,可获得铜精矿品位为18.94%,回收率为85.05%的浮选指标。     

云南某高硫铜金矿石选矿实验研究

为了提高云南某高硫铜金矿石中有益金属的综合回收利用率,对其进行了选矿实验研究.该矿石中铜品位为5.14%、硫品位为16.96%、金品位为0.3 g/t.针对其矿石特点,采用浮选混浮铜硫、磁选铜硫分离、重选富集含金铜精矿的浮选-磁选-重选联合工艺流程,最终得到3个精矿产品.闭路实验获得了较好的指标,铜精矿Ⅰ铜品位为28.64%,含金1.21 g/t;铜精矿Ⅱ铜品位为25.31%,含金0.64 g/t,铜总回收率为98.53%;硫精矿中硫品位为39.93%,回收率为46.08%;可计价金的回收率为30.43%.该工艺在不添加石灰的情况下实现了铜硫的高效分离.     

云南某低品位铅锌硫化矿选矿工艺

对云南某低品位铅锌硫化矿进行了选矿工艺实验研究,采用优先浮选工艺和所选药剂制度处理该矿石.结果表明,该矿具有有价矿物共生关系紧密、嵌布粒度细的特点,其铅、锌品位分别是1.29%和5.63%,实现了铅、锌分离,获得铅品位、回收率分别为51.56%和78.58%的铅精矿和锌品位、回收率分别为46.12%和78.36%的锌精矿.     

浅谈菱镁矿和铝矾土的提纯

菱镁矿和铝矾土是生产耐火材料的主要原料,由于多年的无序开采,优质矿石越来越少.选用合理的选矿流程,先进的选矿技术,提纯低品级耐火原料,综合利用现有资源,是今后的研究课题和发展方向.对菱镁矿浮选厂的工艺技术改造进行了试验研究,将"二反一正"脱硅浮选流程改为"全反"浮选流程,将反浮选扫选尾矿和尾矿分选后所得中矿返回再选,使浮选技术更先进,工艺更合理,精矿产率提高15%,精矿品位提高0.38%,选矿废水全部回收利用,实现废水零排放.菱镁矿风选和铝矾土选矿提纯应由试验研究转向生产应用,形成生产力.镁精矿粉的后序加工选用先进的生产工艺和节能煅烧窑炉,降低能耗44%.     

罗马尼亚开展低品位硫矿的利用工作

罗马尼亚正在进行本国火山型低品位硫矿的利用,以补充本国硫铁矿资源的供给。 硫矿床位于罗马尼亚东北部。矿石含硫15～19％、含硫铁矿5～7％。矿石经过破碎、研磨、浮选、压热、过滤、重力分离等过程制得产品硫磺。矿石经破碎研磨至80％通过200目;用水玻璃、石灰,煤油和乙醇作浮选剂,浮选阶段得含硫55～60％的精矿,回收率80～     

剪切搅拌絮凝浮选回收晋宁低品位堆存磷矿

为了利用晋宁磷矿堆存的低品位高硅质胶磷矿,进行了剪切絮凝浮选试验,研究了剪切搅拌时间、搅拌转速、不同形状及直径的叶轮对选别指标的影响.在浮选搅拌转速为2500 r/min、搅拌时间为8 min时,获得了 P2O5回收率为88.83％、P2O5品位为22.01％的粗选精矿.不同形状及直径的叶轮对剪切絮凝浮选指标的影响不同...     

云南某煤系硫铁矿煤硫综合回收工艺研究

为了有效利用云南某地煤系硫铁矿,采取选煤与选硫铁矿的综合回收方案.在矿石化学多元素分析以及硫形态分析的基础上,进行了螺旋溜槽—摇床重选试验、浮选试验.试验最终采用浮选闭路试验流程,先浮选煤,单独浮选出中矿(该产品并入尾矿),再浮选硫铁矿,最后得到了产率5.38％,碳品位40.32％,含硫7.05％,碳回收率33.76％的煤精矿;产率24.00％,硫品位47.59％,含碳9.64％,硫回收率72.74％的硫精矿,实现了煤和硫铁矿综合回收的目的.     

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.     

Methyl 2,4,6-decatrienoates Attract Stink Bugs and Tachinid Parasitoids

Halyomorpha halys (Stål) (Pentatomidae), called the brown marmorated stink bug (BMSB), is a newly invasive species in the eastern USA that is rapidly spreading from the original point of establishment in Allentown, PA. In its native range, the BMSB is reportedly attracted to methyl (E,E,Z)-2,4,6-decatrienoate, the male-produced pheromone of another pentatomid common in eastern Asia, Plautia stali Scott. In North America, Thyanta spp. are the only pentatomids known to produce methyl 2,4,6-decatrienoate [the (E,Z,Z)-isomer] as part of their pheromones. Methyl 2,4,6-decatrienoates were field-tested in Maryland to monitor the spread of the BMSB and to explore the possibility that Thyanta spp. are an alternate host for parasitic tachinid flies that use stink bug pheromones as host-finding kairomones. Here we report the first captures of adult and nymph BMSBs in traps baited with methyl (E,E,Z)-2,4,6-decatrienoate in central Maryland and present data verifying that the tachinid, Euclytia flava (Townsend), exploits methyl (E,Z,Z)-2,4,6-decatrienoate as a kairomone. We also report the unexpected finding that various isomers of methyl 2,4,6-decatrienoate attract Acrosternum hilare (Say), although this bug apparently does not produce methyl decatrienoates. Other stink bugs and tachinids native to North America were also attracted to methyl 2,4,6-decatrienoates. These data indicate there are Heteroptera in North America in addition to Thyanta spp. that probably use methyl 2,4,6-decatrienoates as pheromones. The evidence that some pentatomids exploit the pheromones of other true bugs as kairomones to find food or to congregate as a passive defense against tachinid parasitism is discussed.     

2007～2008年世界塑料工业进展

收集了2007年7月～2008年6月世界塑料工业的相关资料,介绍了2007～2008年国外塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况.按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、特种工程塑料(聚苯·硫醚、液晶聚合物、聚醚醚酮)、通用热固性树脂(酚醛、聚氨酯、不饱和聚酯树脂、环氧树脂)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍.     

2005～2006年国外塑料工业进展

收集了2005年7月～2006年6月国外塑料工业的相关资料,介绍了2005—2006年国外塑料工业的发展情况。提供了世界塑料产量、消费量及全球各类树脂生产量以及各国塑料制品的进出口情况。作为对比,介绍了中国塑料的生产情况。按通用热塑性树脂（聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂）、工程塑料（聚酰胺、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚）、通用热固性树脂（酚醛、聚氨酯、不饱和树脂、环氧树脂）、特种工程塑料（聚苯硫醚、液晶聚合物、聚醚醚酮）的品种顺序,对树脂的产量、消费量、供需状况及合成工艺、产品开发、树脂品种的延伸及应用的扩展作了详细的介绍。