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1.
抗红外-毫米波双模发烟剂烟幕性能研究   总被引:4,自引:0,他引:4  
为提高抗红外-毫米波双模发烟剂烟幕的衰减性能,以已研制出的发烟剂为基础,实验研究了不同插层物质的可膨胀石墨对所成烟幕3~5μm、8~14μm及3mm、8mm波衰减性能的影响,并从插层物质热分解及氧化能力和膨胀石墨结构等方面对结果进行了分析。结果表明:不同插层物质的可膨胀石墨对烟幕红外、毫米波衰减性能影响很大,其中,分别以CH3COOH、H2SO4、HNO3插层的可膨胀石墨制备的发烟剂衰减效果较好。  相似文献   

2.
欧俊 《广西科学》2004,11(4):337-338
用固相合成方法制备Ba(In0.5Nb0.5)O3。钙钛矿型复合氧化物,并通过XRD方法对产物的物相、形貌和组成进行表征。结果表明,产物为立方钙钛矿结构,粒度为6~10μm的多晶粉末,晶胞参数为a=0.4138nm,空间群为Pm^-3m,衍射数据指标化可靠因子F8=17.6(0.037,12)。  相似文献   

3.
目前发现羟基脉泽的星系都为亮或极亮的红外星系,但在许多(极)亮红外星系中并未探测到羟基脉泽辐射,这可能意味着羟基脉泽寄主(极)亮红外星系具有某些独特的特性.文章利用Spitzer红外卫星的测光数据,研究羟基脉泽寄主星系的中红外特性.通过统计对比分析羟基脉泽寄主星系和非羟基脉泽寄主星系(即未探测到羟基脉泽辐射的星系)在3. 6μm、4. 5μm、5. 8μm、8μm和24μm波段的辐射光度和谱指数、中红外能谱分布,及其与羟基脉泽光度的关系,结果发现:(1)非羟基脉泽样本的3. 6μm辐射光度明显大于羟基脉泽样本;(2)羟基脉泽样本的谱指数较大,能谱分布的对比显示羟基脉泽的光谱更陡(8μm~24μm);(3)羟基脉泽光度与中红外24μm的光度存在较弱的正相关(R~0. 36),间接支持羟基脉泽辐射的远红外辐射抽运机制.  相似文献   

4.
TiSiW12O40/TiO2催化合成肉桂酸甲酯   总被引:5,自引:0,他引:5       下载免费PDF全文
采用高压微波辐射技术,以固载杂多酸盐TiSiW12O40/TiO2为多相催化剂,通过甲醇和肉桂酸反应合成肉桂酸甲酯。实验结果表明,TiSiW12O40/TiO2是合成肉桂酸甲酯的良好催化剂,最佳反应条件为:n(醇):n(酸)=5:1,催化剂用量为反应物料总质量的2.0%,微波功率729W,辐射时间3min.产品平均收率97.4%。  相似文献   

5.
云层红外表观辐射模型的研究   总被引:4,自引:0,他引:4  
在前人对云层红外辐射与反射模型研究的基础上,建立了导引头实际接收的表观光谱辐射亮度(包含云层辐射和反射、天空背景与路径等效辐射)模型,适用于导引头远离云层以及处于云层中的情况.通过傅里叶光谱辐射计对几种远离云层的中、低云表观辐射亮度进行了实际测量,并与模型计算数据进行对比.结果表明:在3~5μm和8~12μm波段,模型计算与实际测量结果具有较好的一致性,可以用于导引头的模拟分析.  相似文献   

6.
该文针对3~5μm和8~14μm波段,以Ba(NO_3)_2-Mg-C_(42)H_(48)O_7和PTFE(聚四氟乙烯)-Mg-C_(42)H_(48)O_7为基础配方,开展了配方组成、质量流率、燃烧温度对红外辐射烟火剂辐射强度影响的试验研究,并讨论了有关试验结果。文中指出PTFE是3~5μm和8~14μm波段都具有较高辐射强度的良好氧化剂,而可燃物C对于具有选择性辐射的富燃配方不能显著提高3~5μm和8~14μm波段的辐射强度;提高质量流率达一定程度后有效辐射率则下降;高温对提高近红外辐射强度适宜,但对远红外不可取。  相似文献   

7.
玻璃陶瓷是固化处理中、高放废物和α废物较为理想的候选材料之一。研究了特定条件下制备的CaO-ZrO2-TiO2-Al2O3-B2O3-SiO2体系玻璃陶瓷在水淬和空气中自然冷却的两种冷却制度对其结晶行为和显微结构的影响,用粉末浸泡实验方法测试了其化学稳定性。结果表明:自然冷却形成的玻璃陶瓷晶相主要是ZrSiO4和ZrTiO4;在25~70℃范围内,温度对玻璃陶瓷浸出率无明显影响,90℃下浸出率比25℃,40℃,70℃的浸出率高一个数量级;7 d元素总的归一化浸出为1.87 g/m2。  相似文献   

8.
介绍了一种用于红外动态场景生成的新型可见光/红外图像转换器芯片.采用离子刻蚀工艺制作芯片的吸收辐射膜,其可见光波段吸收率可以达到98.5%以上,3~5μm波段的红外发射率可以达到0.73,8~12μm波段的发射率达到0.82.测试证明,此吸收辐射膜完全满足红外图像转换芯片的应用要求.  相似文献   

9.
以Ca(NO3)2.4H2O,Co(NO3)2.6H2O和CO(NH2)2为原料,采用均匀沉淀法制备Ca2Co2O5粉体材料。采用FT-IR,TG-DSC,XRD和SEM等手段对样品进行表征,并探讨均匀沉淀法的制备机理。研究结果表明:采用均匀沉淀法,在摩尔比n[CO(NH2)2]:n[Ca2+/Co2+]=4,阳离子浓度比[Ca2+]:[Co2+]=0.200:0.125,加热时间t为3 h时,可获得一定化学组成的前躯体;前驱体于800℃保温8 h后,可获得颗粒粒度为1μm、分布均匀的片状Ca2Co2O5粉体。  相似文献   

10.
以机械活化碱分解黑白钨混合中矿及常压碱煮钨渣所得高杂粗钨酸钠溶液(m(As)/m(WO3)=(0.32~2.94)×10-3,m(Si)/m(WO3)=(1.26~5.84)×10-3)为原料进行钨酸钠结晶过程除砷、硅等杂质的研究,分析了结晶率及氧化铝的添加量对除杂效果的影响.试验结果表明除杂效果与结晶率有关,当结晶率为80%~90%时,除砷率和除硅率均可达90%以上,对m(As)/m(WO3)和m(Si)/m(WO3)分别为3.21×10-4和2.41×10-3的料液而言,除杂后的精液中m(As)/m(WO3)和m(Si)/m(WO3)可分别降至3.50×10-5和3.56×10-4以下.添加Al2O3可明显改善结晶过程中的除杂效果,且Al2O3经化学改性处理后,活性增强,除杂效果更好;在相同条件下,与不加铝盐相比,添加活性Al2O3可使精液中的杂质含量明显降低,除砷率由88.48%增加到94.65%,除硅率由89.77%提高至97.74%.  相似文献   

11.
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.  相似文献   

12.
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.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
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.  相似文献   

14.
何延凌 《科技信息》2008,(4):258-258
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.  相似文献   

15.
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.  相似文献   

16.
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.  相似文献   

17.
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.  相似文献   

18.
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。  相似文献   

19.
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.  相似文献   

20.
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.  相似文献   

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