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1.
阻燃重组竹燃烧中的烟气毒性特征及抑烟性能   总被引:1,自引:0,他引:1  
【目的】了解阻燃重组竹在燃烧时产生的烟雾情况和抑烟性能,为减少建筑火灾发生时的人员伤亡和财产损失提供参考。【方法】以竹束、复配阻燃剂等为原料制备了阻燃重组竹,采用锥形量热仪研究了其燃烧中的烟气特征、毒性情况及抑烟性能。【结果】与非阻燃重组竹相比,阻燃重组竹总烟释放量(TSR)的峰值降低了30.5%,比消光面积(SEA)的峰值降低了40.5%,烟释放速率(RSR)的峰值降低了27.8%,一氧化碳(CO)质量分数的峰值降低了74.7%,CO产率的均值降低了68.8%,二氧化碳(CO2)质量分数的峰值降低了21.4%,CO2产率的均值降低了35.1%。【结论】阻燃重组竹在燃烧中的产烟量和烟气毒性都明显低于非阻燃重组竹,复配阻燃剂具有显著的抑烟和降毒作用。  相似文献   

2.
针对风力发电机组塔架高耸结构稳定性问题,结合仿生结构设计理论,将竹子纤维束引入塔架结构,研究通过仿竹结构设计提高塔架稳定性的方法.以2 MW风力发电机组塔架为研究对象,采用层次分析法对竹子与塔架的相似度进行计算,验证生物选型的合理性.通过研究竹子纤维束特征与竹身稳定性的关系,设计出具有4根加劲肋的仿竹塔架.应用有限元数值分析方法对仿竹塔架和原型塔架的静态和动态效能进行分析,结果表明:仿竹塔架的塔顶位移和最大应力相较原型塔架分别降低了2.27%和13.48%,仿竹塔架前两阶固有频率相较原型塔架提升了1.31%和1.58%,仿竹塔架结构整体稳定性提升了1.4%.验证2 MW风力发电机组塔架仿竹设计的可行性可为后续塔架结构设计提供新的方法.  相似文献   

3.
【目的】大熊猫作为“国宝”级的珍稀濒危物种,迁地保护过程中受到食竹资源的限制。对大熊猫分布区以外的潜在食竹的营养组成进行研究,与主食竹中的营养成分进行比较,筛选出大熊猫潜在的可食竹,为大熊猫的迁地保护和保护区竹种的引种培育提供依据。【方法】以西南林业大学竹园中箭竹属的云南箭竹(Fargesia yunnanensis)、元江箭竹(F. yuanjiangensis)、扫把竹(F. fractiflexa)和棉花竹(F. fungosa),簕竹属的佛肚竹(Bambusa ventricosa)、青皮竹(B. textilis)、孝顺竹(B. multiplex)和绵竹(B. intermedia),慈竹属的慈竹(Neosinocalamus affinis),牡竹属的大叶慈竹(Dendrocalamus farinosus)等10种竹为研究对象,分析了竹叶中粗蛋白、粗脂肪、粗纤维、粗灰分、无氮浸出物、总能、总磷、钙、能量蛋白比等9个指标,探讨竹叶中主要营养成分的季节性变化。【结果】竹叶营养含量中粗蛋白最高的为大叶慈竹(19.54±2.76)%,最低的为元江箭竹(11.64±0.70)%,10种竹叶粗蛋白季节性变化明显; 粗脂肪以孝顺竹的最高(3.59±0.32)%,青皮竹的最低(1.91±0.76)%,粗脂肪季节性变化明显; 粗纤维以棉花竹的最高(43.29±4.10)%,慈竹的最低(37.58±2.45)%,粗纤维的季节性变化不明显; 竹叶总能的季节性变化不明显; 能量蛋白比以元江箭竹的最高((162.44±10.17)kJ/g),元江箭竹、棉花竹、孝顺竹、云南箭竹的能量蛋白比显著高于慈竹、大叶慈竹、佛肚竹和青皮竹的(P <0.05); 10种竹叶中钙质量分数为(0.85±0.05)%~(0.93±0.07)%,钙季节变化不明显; 总磷质量分数为(0.15±0.01)%~(0.27±0.03)%,粗灰分质量分数为(12.06±4.32)%~(16.16±3.80)%,总磷和粗灰分的季节性变化明显。【结论】通过与大熊猫主食竹营养成分比较,发现云南箭竹、元江箭竹、扫把竹、慈竹和孝顺竹等5种竹子从营养组成上符合大熊猫主食竹的需求,将在实际饲养中进一步验证大熊猫对其喜食性。  相似文献   

4.
以聚乙二醇单甲醚-1200(MPEG 1200)与甲基丙烯酸(MAA)为原料,通过直接酯化反应制得聚羧酸类减水剂活性大单体聚乙二醇单甲醚甲基丙烯酸酯(MPEGMA 1200).通过正交实验,评价酸醇摩尔比、反应温度、催化剂质量分数(以聚乙二醇单甲醚质量计)、携水剂质量分数(以反应总质量计)、阻聚剂质量分数(以甲基丙烯酸质量计)、酯化时间对酯化率和双键摩尔分数的影响,确定合成MPEGMA 1200的最佳工艺条件,即酸醇摩尔比为2.0∶1,阻聚剂质量分数为2.5%,催化剂质量分数为4%,携水剂质量分数为40%,反应温度为130℃,反应时间为6h.在此条件下,其酯化率达到98.9%,双键摩尔分数为91.1%.  相似文献   

5.
以环氧氯丙烷、三甲胺、浓盐酸为原料 ,合成了 3 氯 2 羟丙基三甲基氯化铵。研究结果表明 ,最佳合成工艺条件 :环氧氯丙烷与三甲胺盐酸盐的量之比为 0 .95∶1,反应 pH起始值为 7.5~ 8.0 ,反应温度采用分段 (10 ,35℃ )控制。使用合适的催化剂 ,反应收率可达 96 %以上。对三甲基氯化铵溶液中的微量有机杂质环氧氯丙烷和 1,3 二氯丙醇进行了分析 ,并采用连续水汽精馏对产品进行了纯化处理。纯化后的产品中 ,三甲基氯化铵的质量分数为6 9% ,环氧氯丙烷的质量分数小于 0 .0 0 0 5 % ,1,3 二氯丙醇的质量分数小于 0 .0 0 15 %。  相似文献   

6.
以交联聚二甲基硅氧烷(PDMS)作为网络I,聚丙烯酸酯(PA)作为网络II,合成了互穿聚合物网络型(IPNs)乳液.通过探究网络I的催化剂十二烷基苯磺酸(DBSA)质量分数、交联剂正硅酸四乙酯(TEOS)质量分数,网络II的引发剂过硫酸钾(KPS)质量分数等因素,优化合成工艺,并分析IPNs胶膜的力学性能、微观形态、热失重性能.结果表明,IPNs乳液最佳合成工艺为制备网络I时DBSA质量分数为10%、TEOS质量分数为3%,制备网络II时KPS质量分数为0.3%~0.5%.将IPNs乳液应用于涂料印花,印花织物手感柔软,于低温烘干即具有良好的耐摩擦牢度,无需焙烘.  相似文献   

7.
竹类研究进展   总被引:18,自引:1,他引:17  
自古以来竹子一种重要的自然资源,在人们的日常生活中得到了广泛的应用,随着竹材加工工艺的不断改进,以竹子为原料的新产品层出不穷,竹材的工业化利用,使竹子已经不再是“穷人的木材”,竹制精品已称豪华,而竹子的化学利用将成为开拓高附加值竹产品的有效途径,在基础理论研究方面,竹子生物多样性的研究成为新的热点。竹林的生太民功能及其在可持续发展中的重要性愈来愈受到国际社会的广泛关注。在拉丁美洲和非洲,以及在没有天然竹林分布的欧洲和北美洲都日趋注重对竹类的研究与开发利用,现代生物学技术为分子水平揭示竹类植物系统发育和个体发育的机制提供了更有效的手段。  相似文献   

8.
实木复合门用柞木单板的脱色工艺   总被引:1,自引:0,他引:1  
研究了实木复合门用柞木单板脱色处理的工艺,并通过正交试验对木材脱色的主要因素进行了分析,确定了工艺参数:质量分数为5%的次氯酸钠和质量分数为2%的草酸组成氧化型复合脱色剂,处理温度为室温,处理时间为2 h.  相似文献   

9.
研究超高压处理(超高压作用压力和超高压作用时间)对降脂乳化肠滴水损失的改善作用。对不同脂肪质量分数、不同超高压作用压力及不同超高压作用时间的乳化肠进行单因素实验,利用滴水损失的测定方法来评定样品发生的品质变化。再采用响应面分析法优化乳化肠脂肪质量分数(15%,20%,25%)、超高压作用压力(150,200,250MPa)和超高压作用时间(5,6,7min)的工艺参数,建立工艺参数与滴水损失的二元回归方程。以超高压作用压力、超高压作用时间和脂肪质量分数为自变量,分别以滴水损失为响应得到的二元回归模型拟合度高,脂肪质量分数、超高压作用压力和超高压作用时间的交互作用对乳化肠的滴水损失影响显著(p<0.05)。新型超高压降脂乳化肠的最佳工艺条件为超高压作用压力198.47MPa,超高压处理时间5.92min,脂肪质量分数20.51%。与未经超高压处理的脂肪质量分数较高的对照组相比,经超高压处理的降脂乳化肠的滴水损失降低了9.71%。研究结果可为低脂肉制品的开发提供参考。  相似文献   

10.
以均匀设计法安排试验,对大豆油在酯交换反应下制备生物柴油的工艺进行了研究.为获得最优制备工艺参数,考查了n(醇)∶n(油)(3∶1~8∶1)、催化剂质量分数(0.4%~1.4%)、反应温度为(45~70℃)、反应时间(40~140min)及其交互作用对生物柴油产率和原料转化率的影响.结果表明:n(醇)∶n(油)、催化剂用量可显著地影响生物柴油的产率和原料转化率.同时甲醇与反应温度、催化剂与反应时间之间存在对抗效应,而甲醇与反应时间、催化剂与反应温度、反应温度与反应时间之间则存在协同作用.利用回归分析和BP神经网络,确定最优工艺参数为:n(醇)∶n(油)=6∶1;催化剂质量分数1.0%;反应温度45℃;反应时间30min.经液相色谱仪测定,生物柴油产率高达97.6%.  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.
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   

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.
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   

15.
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   

16.
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   

17.
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   

18.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

19.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

20.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

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