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1.
珍珠花丛生芽的诱导及生根条件的研究   总被引:5,自引:0,他引:5  
诱导珍珠花(Staphylea bumalda DC)丛生芽的最佳培养基为MS基本培养基附加NAA0.2mg.L^-1和BA5MG.l^-1,无菌苗在1/2MS培养基中附加NAA1mg.L^-1、活性碳0.45g.L^-1、硫胺素1mg.L^-1、蔗糖20g.L^-1能长根形成完整植株。  相似文献   

2.
复合型纳滤膜的制备及表征   总被引:12,自引:0,他引:12  
在聚砜基膜上用界面聚合法制备了两种复合型纳滤膜PA01和PA02。在0.3MPa下,PA01膜对MgSO4溶液和FeCl3溶液的脱直 96.0%和78.0%,水通量分别为8.5(L.m^-2.h^-1)和7.9(L.m^-2.h^-1);PA02膜对MgSO4ipwkiyw (2.0g.L^-1)和CaCl溶液(0.5g.L^-1)的脱盐率分别为98.0%和88.8%,水通量分别为1.0(L。m^  相似文献   

3.
应用火焰原子吸收光谱法(FAAS)直接测定不同妊周孕妇及婴儿脐血血清中微量元素含量,并以标准物牛血清作方法质控,监测结果有效地用于产前干预.在最佳实验条件下,各元素的精密度(SR).检出限(ρDL/mg·L-1)和标准加入回收率(Y)分别为:Zn,4.10%,956×10-3,99.0%~103%;Cu,3.50%,0.037,97.0%~101%;Fe,4.27%,0.043,99.0%~103%;Ca,2.29%,0.020,99.0%~101%;Mg,2.29%,3.88×10-3,97.0%~103%.该方法具有用样量少、简便准确、高精密度等特点.  相似文献   

4.
Cl-和SO2-4对厌氧废水处理的抑制阈值   总被引:4,自引:0,他引:4  
用人工配制高浓度有机废水分别研究了Cl^-和SO4^2-对厌氧生物废水处理的抑制作用和抑制阈值。在全混流厌氧恒化器和上流式厌氧污泥床(UASB)反应器中分别得到了对厌氧消化基本无抑制作用(全混流恒化器:Cl^-〈4.5g/L,SO4^2-〈1.8g/L;UASB:Cl^-〈7.2g/L,SO4^2-〈3.0g/L);轻度抑制(全混流恒化器:Cl^-=4.5 ̄6.0g/L,SO4^2-=1.8 ̄3.  相似文献   

5.
温度和光照等因素对荸荠试管球茎形成的影响   总被引:3,自引:0,他引:3  
“桂林马蹄”和“余杭大红袍”的荸蔼茎尖接种在MS+KT0.1mg.L^-1地培养基上15d后,诱导出的试管苗在MS+6-BA2.0mg.L^-1+NAA1.0mg.La^-1培养基上增殖培养25d后,再经60d培养可诱导出试管球茎,供试两品种试管球茎形成的最适增减其分别为MS+6-BA1.0mg.L^-1+蔗糖90g.L^-1和MS+6-BA0.8mg.L^-1+蔗糖90g.L^-1,最适培养条件  相似文献   

6.
研究了铅对原子吸收光谱法测定锑及铜的干扰及其消除方法,提出了测定铅钙合金中锑、铜的新方法.测定锑的特征浓度为0.4mg/L(1%),线性浓度范围0~30mg/L;测定铜的特征浓度为0.037mg/L(1%),线性浓度范围为0~3mg/L;方法简便快速,选择性好,经标样分析表明,结果的准确度及精密度均符合要求.  相似文献   

7.
用人工配制高浓度有机废水分别研究了Cl-和SO2-4对厌氧生物废水处理的抑制作用和抑制阈值.在全混流厌氧恒化器和上流式厌氧污泥床(UASB)反应器中分别得到了对厌氧消化基本无抑制作用(全混流恒化器:Cl-<4.5g/L,SO2-4<1.8g/L;UASB:Cl-<7.2g/L,SO2-4<3.0g/L);轻度抑制(全混流恒化器:Cl-=4.5~6.0g/L,SO2-4=1.8~3.3g/L;UASB:Cl-=7.2~8.2g/L,SO2-4=3.0~4.1g/L);中度抑制(全混流恒化器:Cl-=6.0~13.8g/L,SO2-4=3.3~6.5g/L;UASB:Cl-=8.2~10.0g/L,SO2-4=4.1~6.0g/L)和重度抑制(全混流恒化器:Cl->13.8g/L,SO2-4>6.5g/L;UASB:Cl->10.0g/L,SO2-4>6.0g/L)的不同Cl-和SO2-4浓度范围.  相似文献   

8.
在pH=5-12的乙醇水溶液中,Cu62+与丙酮醛双,N.N‘-缩氨基硫脲可形成1:1型络合物,其λmax=488nm,ε488=1.09×10^4L.mol^-1.Cu^2+浓度在0-5.0mg/L内服从比耳定律;若用氯仿萃取后测定,其ε488=1.77×10^5L.mol^-1cm^-2,Cu^2+浓度在0-0.50mg/L内服从比耳定律。  相似文献   

9.
研究了以1mol.L^-1NH4SCN为介质,甲基异丁基甲酮萃取,4mol.O^-1硝酸反萃取火焰原子吸收光谱水相测定微量钴的方法,钴量在0-5mg.L^-1范围内呈良好的线性关系,检出限为0.070mg.L^-1,相对标准偏差为1.17%,该方法适用于腺苷钴胺片中微量钴的测定。  相似文献   

10.
提出了一种无氰电沉积光亮铜锡合金的新工艺,其溶液组成及操作条件为:Na3C6H5O.2H2O90-120,Na2EDTA.2H2O25-35,稳定剂WDZ-94310-15?CuSO4.5H2O20-40,SnCl2.2H2O20-40g.L^-1;溶液的pH=5-6,Dk=10-150A.m^-2,T=50-60℃,在上述条件下可获得含锡量为5%-15%的光亮、细致、均匀的铜锡合金沉积层。  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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