磷石膏掺量及烧成制度对硫铝酸盐水泥熟料物理性能的影响

以磷石膏、石灰石、铝矾土为原料配制硫铝酸盐水泥熟料,研究了磷石膏掺量及烧成制度对硫铝酸盐水泥熟料性能的影响。结果表明:磷石膏可以取代天然石膏配置硫铝酸盐水泥熟料,磷石膏掺量在14.22%时,熟料物理性能最优。熟料烧成温度应控制在1320℃~1350℃范围内。     

不同来源的硫在硅酸盐水泥熟料中的存在形态及分布特性

分析研究三个不同生产线的硅酸盐水泥熟料,其中Z厂采用高硫煤进行熟料的煅烧,且其原料中的碱含量不高,XRD测试结果显示该线熟料中的硫主要以硫铝酸盐的形式存在;J、H两厂原料石灰石中低温可分解硫含量较高,且两厂原料中的碱含量相对较高,虽然采取了不同的固硫方式,但XRD测试显示两厂的硫主要以硫酸盐(K_2SO_4)的形式固溶于熟料之中;采用电子探针技术对Z、J两厂的熟料样品进行微观分析,虽然硫的存在形式不同,但硫元素都仅存在于A矿、B矿之中,而且这些固溶了硫元素的矿相较没有固溶的矿相在感官色泽上发生了变化。     

高镁石灰石煅烧制度对熟料性能及熟料中方镁石形成的影响

采用高镁石灰石原料煅烧熟料通常会因熟料中方镁石含量多而造成水泥安定性不良,这严重制约了水泥行业的发展,本文借助化学分析、岩相分析、胶砂试验研究、光学显微镜,XRD、SEM等检测方法,探讨了XDL系统与NSP系统煅烧高镁石灰石原料生产熟料的适应性情况.对采用XDL系统煅烧高镁石灰石原料与NSP系统煅烧高镁石灰石原料的对比研究结果表明:XDL系统煅烧的熟料强度增幅快,方镁石含量低,尺寸小,熟料中生成了更多的A矿和B矿,且A矿晶粒形状规则,平均尺寸达30 μm;采用NSP系统煅烧的熟料中A矿以M3型为主,XDL系统煅烧高镁石灰石原料能够将熟料中A矿稳定为M1型.     

钼尾矿制备贝利特水泥熟料早期性能研究

本文以钼尾矿为主要原料制备贝利特水泥熟料.并通过强度、X射线衍射、扫描电镜等测试,研究了原料配比和石膏活化剂掺量对水泥熟料性能的影响.实验结果表明:以质量分数为23.3％钼尾矿、3.4％的河砂和73.3％的石灰石为原料,再添加1.5％的石膏作活化剂,在1350℃下煅烧0.5h制得的贝利特水泥熟料强度最高.钼尾矿的掺加对贝利特水泥熟料主要矿物种类没有影响.加入石膏可促进熟料烧成,且生成了少量硫铝酸钙,使得熟料强度明显增加.     

两个不同品种硅酸盐水泥熟料中硫存在形式及其分布特性研究

本文主要采用XRD分析和电子探针分析技术,选取了典型的4个硅酸盐水泥生产线的熟料(Y、H厂为白色硅酸盐水泥熟料,Z、J厂为普通硅酸盐水泥熟料),研究两个不同品种的硅酸盐水泥熟料中硫的存在形式及其分布特性。研究结果显示:Y、H厂白水泥熟料中的硫主要以硫酸钙的形式存在,Z、J厂普通硅酸盐水泥熟料中的硫主要以硫酸盐或硫铝酸钙的形式存在。两种硅酸盐水泥熟料中硫的分布特性相同点是硫元素或硫的化合物均主要存在于黑色的A矿和B矿;不同点是白色硅酸盐水泥熟料中间相中也有大量硫的存在,灰色的A矿和B矿中含有少量硫,而普通硅酸盐水泥熟料中间相中极少存在硫,灰色A矿和B矿中不含硫(以本次电子探针图判断)。     

磷石膏部分分解制备贝利特硫铝酸盐水泥的探究

利用磷石膏分解率高的特点,将预先煅烧后分别达到73.82％和80.15％分解率的磷石膏与矾土和石灰石进行配料烧制贝利特硫铝酸盐熟料,探讨部分分解磷石膏用于制备贝利特硫铝酸盐水泥的可行性.理论计算结果表明,当磷石膏分解率达到80.15％,SO2可以达到有实用价值的收集浓度;试验结果表明,利用部分分解的磷石膏制备的贝利特硫铝酸盐水泥早期水化放热量偏低,硬度也略微低于天然石膏制备的贝利特硫铝酸盐水泥的硬度,但对早期强度无明显的不利影响.可以认为,部分分解磷石膏可以用于制备贝利特硫铝酸盐水泥.     

利用含稀土元素原料煅烧水泥熟料的几个问题

利用含微量镧系元素的粘土或工业废渣煅烧水泥熟料，已成功地应用于工业生产，取得了提高水泥熟料产质量及节能的显著效果。本文就利用含稀土元素原料饭烧水泥熟料的几个问题进行讨论。1稀土元素含量对煅烧熟料的影响以工业用石灰石、粘土、铁粉及煤灰配制水泥生料，生料中稀土     

利用垃圾焚烧飞灰制备硫铝酸盐水泥及其水化放热特征

以城市垃圾焚烧飞灰为主要原料,在实验室电炉里成功烧成了硫铝酸盐水泥熟料.分析了焚烧飞灰掺量、碱度对熟料烧成的影响,研究了烧成熟料的形貌、化学组成,以及掺加一定量的无水石膏配制的硫铝酸盐水泥物理性能及其水化放热特征.结果表明:以焚烧飞灰为主要原料可以煅烧得到理想的硫铝酸盐水泥熟料;生料配比中焚烧飞灰掺量不宜超过30%,所...     

低碱水泥生产途径的探讨

水泥中碱含量主要来自熟料,影响熟料减含量的主要因素是石灰石和粘土质原料中的碱含量。文章通过对石灰石和粘土质原料质量特征的分析,提出了生产低碱水泥的途径,并就旁路放风对降低熟料碱含量的影响作了探讨。     

磷石膏制硫酸联产水泥熟料的竞争力——大型装置设计思路

介绍了以硬石膏为原料生产硫酸联产水泥装置的生产实践,提出了以磷石膏为原料生产硫酸联产水泥熟料的设计构想。通过分析磷石膏品质及原燃材料的预均化,将磷石膏烧制的水泥熟料与石灰石烧制的熟料按一定比例搭配制成水泥;采用新工艺、设备及严格的操作制度,以提高设备的热利用率。按新的设计思路,以磷石膏生产硫酸联产水泥熟料可将生产设备省去一半,投资降低40%以上,窑气中φ(SO2)可提高至10%～12%,回转窑的热效率达45%,熟料热耗6 100～6 500 kJ/kg。     

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。