光子相关光谱法测量超细颗粒的理论研究

光子相关光谱学(PCS)是一项近年来取得较大进展的新应用技术,该技术利用悬浮于介质中的散射体的布朗运动所引起的散射光强涨落现象,能测量粒径范围为3nm～3μm的超细颗粒。本文详述了PCS测粒法的基本理论,综述了各种预测颗粒粒径分布的数据处理方法,并提出了对PCS进一步研究的若干问题。     

膜分散沉淀法制备硫酸钡超细颗粒

将膜分散技术应用于超细颗粒的制备过程,以氯化钡和硫酸钠为原料制备硫酸钡为例,对于膜分散沉淀法制备超细硫酸钡颗粒的影响因素进行了研究,并将膜分散沉淀法与直接搅拌沉淀法相比较。研究结果表明:在同样的反应条件下,直接搅拌沉淀法得到的颗粒成片状,粒度在0.3～1.0 μm;而膜分散沉淀法得到的颗粒球形度好,平均粒径在10～100nm。膜分散沉淀法制备硫酸钡超细颗粒粒度小,粒径分布窄,单分散性好;硫酸钡颗粒粒度随硫酸钠浓度的升高而迅速降低。在膜分散沉淀过程中无需进行搅拌。该方法与直接沉淀法相比具有能耗低、可连续操作、以及粒径可控的优点,是一种高效新型的超细颗粒制备方法。     

基于分维计算的颗粒粒度分析方法

提出了一种基于分形检测超细颗粒粒度的新方法及实现算法,超细颗粒在一定条件下产生布朗运动,通过光电系统记录的图象可看成是群体颗粒无规则漫游的结果,从而可用分数布朗运动模型去描述,对所获取的超强微粒布朗运动图象进行处理,然后按以上分形模型进行逐点的分维计算,再用统计的方法转换为粒度信息,从而实现粒度测量,文中给出了具体的算法及算例。     

利用高温显微镜研究硅砂粒度对玻璃熔化的影响

本文讨论了利用高温热台显微镜对硅砂粒度上限、下限以及细颗粒含量对玻璃熔制过程的影响,确定出符合玻璃生产所需要的最佳硅砂粒度。     

凝胶网格法制备CdS超细颗粒

该文首次利用凝胶网格法制备了ＣｄＳ超细颗粒,测定了样品的等电点及ＴＥＭ粒度分布,ＸＲＤ等性能表征并对结果进行了讨论证明上法简单,易控,具有很强的实用性。     

微细颗粒粒度分析方法与测试技术

超细颗粒由于其具有一系列特殊的性质,在国民经济和国防现代化以及现代高科技领域具有重要价值,有着广阔的应用前景。超细颗粒的测量方法和测试技术则是颗粒研究领域的热点。笔者分析并综述了现代颗粒测试的方法和技术,讨论了这些方法应用于亚微米级超细颗粒的测量时存在的问题和局限。     

超细颗粒悬浊液中声衰减和声速的数值模拟-- 4种模型的比较

分别运用了4种数学模型 ECAH模型、Harker & Temple模型、BLBL模型以及McClements模型研究了声波在超细颗粒悬浊液中传播的衰减和相速度,对各种模型的数值模拟计算结果进行了比较,讨论了各种衰减机制对模拟结果的影响. 结果对将超声方法用于悬浊液和乳剂中的颗粒粒度、浓度测量的实验研究和工程应用均有一定参考价值.     

Photo—Fenton反应产生的羟自由基的研究

报道了用紫外分光光度法间接测定Ｐｈｏｔｏ－Ｆｅｎｔｏｎ反应即利用光激发ＴｉＯ２超细颗粒产生的Ｈ２Ｏ２进行Ｆｅｎｔｏｎ反应。产生的羟自由基。通过对测定结果的分析,得到ＴｉＯ２超细颗粒与光激发ＴｉＯ２超细颗粒产生的羟自由基之间的定性和定量关系,从而为进一步研究纳米材料的光催化氧化机理提供一种简单易行的方法。     

紧密堆积优化炸药粒度级配技术研究

以Dinger-Funk模型和可压缩堆积模型为基础,对炸药进行颗粒级配和堆积密实度的计算;并以黑索今炸药进行实验,验证了计算结果的准确性,探讨了炸药体系中细颗粒添加量对堆积密实度的影响。结果表明,经过粒度级配可以实现炸药粒度分布的优化,用可压缩堆积模型可以很好地预测炸药的堆积密实。在满足紧密堆积——Dinger-Funk粒度分布模型条件下,级配后的堆积密实度度提高了16%;只增细颗粒时,堆积密实度与原材料的粒度分布相关联。     

溶胶-凝胶法合成人造金红石超细颗粒

探讨了文题的方法,研究了反应物与催化剂浓度对凝胶化速度、颗粒大小及分布的影响。结果表明,烷氧基钛在醋酸催化作用下水解和缩聚可制备均匀透明的块状凝胶,经干燥、焙烧得到金红石型的TiO_2超细颗粒。颗粒平均粒度随水含量增加而下降;随水解底物浓度的增加而下降,然后略有上升;随醋酸浓度增加而降低。醋酸根离子浓度不仅作为催化剂,而且作力能形成Ti(OC_4H_9)_x(Ac)_y络合物的配位体而起作用,改善了颗粒粒度的均匀性。凝胶透明度与颗粒的粒度及其分布有关,而与凝胶化时间无关。本法制备的TiO_2颗粒粒度细(20～200nm)、单分散性好且纯度高。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

橡胶颗粒沥青混合料低温抗裂性试验研究

以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Quantitative trait loci （QTLs） for quality traits related to protein and starch in wheat

Quality traits in wheat （Triticum aestirum L.） were studied by quantitative trait locus （QTL） analysis in a recombinant inbred line （RIL） population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross （ChSh）. Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.