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1.
以硝酸铈铵为引发剂,研究了甲基丙烯酸甲酯、丙烯酸乙酯分别与苧麻及亚麻纤维的非均相接枝共聚合反应规律。当[Ce~(4+)]在4.5×10~(-3)~6.5×10~(-3)mol·l~(-1)、[M]在6×10~(-1)~9×10~(-1)mol·l~(-1)、[H~+]在5×10~(-2)~8×10~(-2)mol·l~(-1),30~40℃,反应2~3小时,接枝率较高。  相似文献   

2.
本文分析研究了浙江凫溪香鱼的生长及体型变化规律。体重与体长关系为:W(♀)=6.5317×10~(-7)L~(3.6373);W(♂)=7.3756×10~(-7)L~(3.6073)。体长生长式为:L_t(♀)=204.2360/(1+21.8466e~(-0.3903t)),L_t(♂)=197.5000/(1+23.9079e~(-0.4276t)),体重生长式为:W_t(♀)=121.9960/(1+9691.6601e~(-0.8578t)),W_t(♂)=111.3113/(1+11211.5210e~(0.9184t))。体长、体重最快生长期分别在5月、8月。综合考虑香鱼的生长和肥满度变化规律,认为11月份是其合理起捕期。香鱼的体型变化主要发生在体长75mm之前,其中头长变化规律还证明与其食性的转变阶段有着密切关系。  相似文献   

3.
合成了三(1—苯基—3—甲基—4—三氟乙酰基吡唑啉酮—5)二水合钕(Ⅲ)萃合物。经元素分析确定其组成为Nd(PMTFP)_3·2H_2O,X射线单晶衍射测定了化合物的晶体结构及分子结构。晶体属单斜晶系,P2_1/c空间群,晶体学参数如下:a=17.799(9)×10~(-10)m,b=12.661(6)×10~(-10)m,c=18.691(7)×10~(-10)m,β=102.71(6)~0,v=4108.8(10~(-10)m)~3,Z=4.分子中中心原子钕与八个氧原子成配位键,其中六个氧来自三个双齿配位的PMTFP-基,其余两个氧则由两个水分子所提供,八个氧原子取四方反棱柱型排列在钕的周围。  相似文献   

4.
以生长分析及树干解析法,分析了黑石顶自然保护区马尾松(Pinus massonianaLamb)种群从幼苗幼树至成熟个体的生长特点及规律.①总生物量的增长从幼苗期开始便呈幂函数增长,直至整个生长旺盛期.②最初几年的幼苗,具较高的叶生物量和较低的根生物量(分别占总生物量的30%~60%和20%以下,最低仅6%~7%).和径向生长相比.幼苗高生长较快.③自然生长的2、3年生幼苗的相对生长率分别为3.499×10~(-2)和6.618×10~(-2)g/g·week),净同化率分别为6.310×10~(-2)和0.227(g/g·week).  相似文献   

5.
本文从统计的角度指出在理论上Wein位移定律λ_mΥ=0.29×10~(-2)(m·k)和λ_mT=0.51×10~(-2)(m·k)的形式和内容必须保持一致;从实验的角度确认了Wein位移定律的本来形式应该是λ_mΥ=0.29×10~(-2)(m·k),而不是λ_mT=0.51×10~(-2)(m·k)。  相似文献   

6.
利用2010年9月至2013年8月每季度从福建九龙江口的紫泥、岛美、浮宫3个站点的定置张网和流刺网渔获物中采集的凤鲚样本,分析凤鲚的生物学特性.结果表明:1)九龙江口凤鲚体长分布范围为44~239 mm,优势体长为140~160 mm,体重分布范围为0.20~69.10 g,优势体重为0.20~20 g,体长与体重的关系式为W=1.3×10-6 L3.23(R2=0.88,P<0.01,n=927),体长生长方程为Lt =246.75[1-e-0.65(t+0.21)],体重生长方程为Wt=64.94[1-e–0.65(t+0.21)]3.23 ,由此可将凤鲚看做匀速生长的鱼类;2)凤鲚夏季洄游至九龙江产卵,性成熟以Ⅴ期为主,冬季摄食强度最强;3)凤鲚的总死亡系数、自然死亡系数和捕捞死亡系数分别为2.0、0.67和1.33.结果说明九龙江口凤鲚资源已经处于过度开发状态,需要采取合理的保护和限制捕捞措施.  相似文献   

7.
用高温投下法,通过控制炉内气氛,在铜卡量热计中测定了硼泥及其分解产物的比热容,其值为硼泥 Cp=-1.608+3.279×10~(-3)T+2.847×10~5T~(-2),/(g·x) 硼泥分解产物 CP=0.461+0.633×10~(-3)T+0.510×10~5T~(-2),J/(g·K)其复相关系数分别为0.9920和0.9996.  相似文献   

8.
陈国华  张本 《江西科学》1989,7(1):56-61
鄱阳湖产太湖短吻银鱼以枝角类、桡足类等浮游动物为主要食料.它们天亮开始摄食,夜间停止,白天连续摄食,其援食速度和消化速度都很快.晴天摄食多,雨天摄食少.周年内,在6、10—11、3月份三次出现摄食高峰.正在产卵的雌鱼停止摄食,产卵后,摄食量又大增.  相似文献   

9.
卷口鱼的年龄和生长   总被引:4,自引:0,他引:4  
研究卷口鱼的年龄和生长特点 ,得出卷口鱼的体长与鳞长的关系式为 :L =5 0 974 + 33 15 9R ;体长与体质量的关系式为 :m =1 395 2× 10 - 5L3 10 62 ,以及卷口鱼的生长方程、体质量生长速度 (dm/dt)、体质量生长加速度 (d2 m/dt2 )、体长生长速度 (dl/dt)和体长生长加速度 (d2 l/dt2 )方程  相似文献   

10.
谷氨酸钠热分解过程的研究   总被引:1,自引:0,他引:1  
本文采用热重分析法研究了一水合谷氨酸钠的热分解过程。结果表明:一水合谷氨酸钠的热分解过程分为两个阶段,在105℃开始脱去结晶水,在155℃开始分子内脱水。脱结晶水阶段的动力学参数为n=0.2,E_a=102.2 kJ·mol~(-1),A=1.7×10~7S~(-1);分子内脱水阶段的动力学参数为n=3.2,E_a=322.3kJ·mol~(-1),A=1.1×10~(34)S~(-1)。  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.
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   

15.
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   

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.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

19.
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   

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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