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1.
该文建立了描述液体燃料空气炸药云雾运动规律的模型,给出了云雾膨胀过程3个阶段的速度-半径关系或速度-时间关系,以及云雾中燃料液滴的尺寸估计。  相似文献   

2.
工业碳氢燃料爆轰特性的实验研究   总被引:1,自引:0,他引:1  
在立式激波管中对烯烃(C5H8.68)云雾的爆轰参数进行实验测定,与其它碳氢燃料云雾爆轰进行比较,分析影响爆轰性能的因素。结果表明,该燃料云雾的临界当量起爆能与量浓度比的关系为“U”型曲线,在量浓度比为1.17处,其云雾的临界起爆能最小,在富燃料一侧,量浓度比在一定范围内,爆压为2.6MPa左右,用该燃料代替环氧丙烷(PO)可以相应增加FAE(Fuel—Air-Explosive)武器的威力。  相似文献   

3.
通过对空间量子密钥分配系统成钥率的分析和仿真计算,得出了穿越云雾的量子密钥分配的成钥率与云雾浓度的关系,论证了可以进行有效空间量子密钥分配的云雾浓度上限和对应的气象视距下限.  相似文献   

4.
固体灭火剂在中心抛撒炸药作用下的试验研究   总被引:2,自引:1,他引:1  
对灭火剂在中心抛撒炸药的作用下的抛撒效果进行试验,对不同的比药量进行对比试验,确定合适的范围.同时对灭火剂的质量与抛撒效果的关系进行试验,试验结果证明增加灭火剂质量不能显著增加云雾体积,但是云雾持续时间与灭火剂质量近似成正比例关系.另外,风向、弹体形状等因素对云雾形状也有一定的影响.  相似文献   

5.
采用基于延时分次扫描单光子计数器为探测装置的皮秒时间分辨荧光光谱测试系统研究了菠菜光系统(PS )CP47&RC蛋白复合物光能传递与温度的关系。分别对CP47&RC样品在20,42,48℃下做温度处理后,以脉宽为120ps,重复率为4MHz,波长为514nm的Ar+激光作为光源分别激发处理后的样品,对比研究了菠菜CP47&RC激发能传递速度与温度的关系,发现同一波长,不同温度下能量传递速度不同,48℃时能量传递的速度总体变慢;CP47&RC在42℃温浴处理的情况比较特别。  相似文献   

6.
岩石纵波速度—密度的关系对于指导塔河地区灰岩的勘探开发是非常有必要的。本文选取了该地区22口井中采集到的100块有代表性奥陶系灰岩的岩心样品,基于MTS岩石物理测试系统测量常温常压条件和地层温压条件下的不同流体饱和状态灰岩(205组)的纵波速度、密度等参数,整理数据分析发现Garnder关系式(1974)和Castagna关系式(1993)不能很好地适用于该地区灰岩的速度密度关系,进而采用自适应异常点剔除的速度—密度关系的最佳拟合方法结合异常点剔除合理性分析,得到适用该地区的速度?—密度多项式、指数拟合关系式,该关系式能较好地表示该地区的速度—密度关系,有助于提高该地区的储层预测的准确性和可靠性,具有重要的实际应用价值和理论价值。  相似文献   

7.
安岭公社位于台州、丽水、温州三个地区交界的边远山区。山高谷深,气温低,日照短,层层梯田多在海拔700——1000米的山坡上,一年四季云雾缭绕,素有云雾田之称,一直被认为是连作稻的“禁区”。通过无产阶级文化大革命,毛泽东思想空前大普及,他们认真总结经验教训,掌握客观规律,打了一场粮食翻身仗。1970年,全社种植连作稻1071亩,平均亩产达1062斤,比单季稻平均产量翻了一番。实践使他们深深体会到:毛主席的光辉哲学思想,不仅是观察社会、改造社会的法宝,也是认识自然,改造自然,迅速发展农业生产的强大思想武器。确是辩证法上高山,人变聪明田不懒,战天斗地创奇迹,云雾田里出高产。  相似文献   

8.
在铁饼技术中速度节奏起到了非常重要的作用。对我国优秀运动员宋爱民进行个案分析速度节奏,总结优缺点。运用文献资料法、三维摄像解析法、访谈法、跟队训练法等。研究结果表明:单支撑阶段节奏慢,局部动作中右髋关节速度节奏最快;腾空阶段和过渡阶段速度节奏比较快,这是她的技术优势;最后用力阶段具备优秀运动员的数据指标,左右髋关节的速度相对来说有些慢。整个技术阶段,宋爱民人体重心速度节奏变化表现为:快—快—快—慢—慢;所用时间比例的关系表现为:最长—稍长—最短—短—长。  相似文献   

9.
刘雪岭  张奇 《北京理工大学学报》2018,38(12):1252-1255,1320
针对可燃液体云雾在化工安全生产过程中爆炸敏感性的问题,进行了正烷烃(正己烷/正庚烷/正辛烷/正癸烷)云雾最小点火能变化特征规律的实验研究.利用自行研发的瞬态云雾浓度粒径测量系统和20 L云雾爆炸参数测量系统分别得到汽、液两相云雾浓度粒径和点火实验测量结果.研究结果表明:正烷烃云雾最小点火能均大于其相应纯气相最小点火能;随着云雾粒径的增加,最小点火能呈指数性增长,在0~40 μm粒径范围内,最小点火能随粒径增加了2个数量级.   相似文献   

10.
怪诞云雾     
有些云雾形迹诡秘,有些甚至看上去很普通的云雾却会攻击人,甚至致人神秘失踪。除了UFO,天空中还有许多难以解释的现象。几百年来,许多目击者报导了一些看似普通云雾的怪异行为,或者本身看起来就很怪异的云雾。而且有些报导还来自比较有声望的科学杂志。  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.
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   

20.
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   

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