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1.
In this paper, the influences of different kinds and different amount of mineral admixture to Cl-penetration and diffusion in concrete are studied. The results of experiment show that separate addition of mineral admixture (ground fly ash, slag fines, silica fume) into concrete can improve its resistance to chloride ion penetration and diffusion. Furthermore,the effect of silica fume is the best, fly ash second, and then follows slag fines. Mechanism analysis shows that the pozzolanic effect of mineral admixture improves the interface between the cement and aggregate in concrete, reduces the total porosity, makes pores more smaller, on the other hand it increases the Cl-consolidation capability of concrete with low alkaline C-S-H gel produced. So the resistance to chloride ion penetration of concrete is improved.  相似文献   

2.
陈托兄 《中国农学通报》2011,27(12):153-158
用采自英国苏克塞斯的海滨碱蓬为材料,将铺有滤纸的培养皿中发芽7天的海滨碱蓬幼苗,移栽到育苗盘中溶液培养,用调整过的Hoagland营养液培养海滨碱蓬21天,用150 mmol/L NaCl处理海滨碱蓬0 h、6 h、12 h、24 h、36 h及48 h,测定海滨碱蓬在不同处理时间下根、茎、叶的鲜重、干重及Na+含量。分析Na+吸收速率在48 h内的变化趋势。结果表明,不同处理之间海滨碱蓬Na+吸收速率差异不显著。因此,海滨碱蓬在48 h内的Na+吸收速率基本保持不变,在与Na+吸收途径有关的试验中处理时间设为48 h不仅可以节省人力物力财力,又可以取得事半功倍的良好研究目的。  相似文献   

3.
为了探究氯化镧对不同叶色水稻抗氧化酶活性的影响,研究了不同时期喷施氯化镧溶液对P88S(绿叶)和黄1S(黄叶)的叶绿素含量,以及超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)、丙二醛(MDA)含量的影响。结果表明:100 mg/L的氯化镧能够显著提高P88S和黄1S的抗氧化能力,在分蘖期超氧化物歧化酶活性分别提高31.2%和50%,达413.2μmol/g FW和484.9μmol/g FW;抽穗期过氧化物酶活性分别增加7.5%和30.7%,达199.2μmol/g FW和130.1μmol/g FW,且能显著降低丙二醛的含量,分别降低34%和24.7%,达5.55 nmol/g和5 nmol/g。100 mg/L氯化镧溶液处理后,黄1S相比P88S,超氧化物歧化酶活性在分蘖期、孕穗期和抽穗期分别增加14.8%、3.2%和33.7%,过氧化物酶活性分别增加7.5%、21.1%和18.1%。综合分析表明,喷施100 mg/L氯化镧溶液能够提高不同叶色水稻的抗氧化酶活性及丙二醛含量,从而提高叶片的抗氧化能力。  相似文献   

4.
By adding small amount of dihydrate gypsum (CaSO4·2H2O) and silica fume in steel slag-cement system, steel slag-cement binding materials were prepared. And the dosage of CaSO4·2H2O and silica fume on the properties of steel slag-cement binding materials was studied. Hydration properties and paste structure were investigated by SEM and XRD. The results show that both CaSO4·2H2O and silica fume can improve the strength of steel slag-cement binding materials. Compared with single-doped, compound of CaSO4·2H2O and silica fume has much better effect on strength of steel slag-cement binding materials. The optimum proportion of CaSO4·2H2O and silica fume are 1% and 4%, respectively. The 3 d compressive strength is increased by 59.0%, and the 28 d compressive strength is increased by 36.5%. No matter adding CaSO4·2H2O and silica fume or not, the steel slag-cement binding materials have the same hydration products. However, the content of C-S-H gel and AFt crystals is higher, and the content of Ca(OH)2 crystals is lower in steel slag-cement binding materials containing CaSO4·2H2O and silica fume than those in steel slag-cement binding materials without CaSO4·2H2O and silica fume.  相似文献   

5.
采用二次注入菌液方式,制备不同浓度营养盐处理的MICP (微生物诱导碳酸钙沉淀)胶结砂样。选用巴氏芽孢杆菌作为固化细菌,采用单一浓度(0.5、1.0 mol/L)和多浓度相结合(前期采用0.5 mol/L,后期采用1.0 mol/L)的处理方式注射营养盐(尿素/氯化钙混合液),研究多浓度营养盐结合处理方式对微生物固化砂土强度及均匀性的影响。基于试验测试分析了固化砂土试样不同区间段的强度、弹性模量以及碳酸钙含量。试验结果表明,多浓度营养盐处理方式对固化砂土试样的强度及碳酸钙含量有明显影响;多浓度营养盐结合处理方式能够保证试样有较好的均匀性条件下获得较高强度及弹性模量。基于多浓度营养盐处理方式,探讨分析了影响试样强度和均匀性的基本因素。  相似文献   

6.
This paper developed a spectrophotometric determination of micro amounts of Gallium with butylrhodamineB in lead-zinc mineral. Large amounts of interfering ions Zn 2+ ?Pb 2+ ?Al 3+ ?Ca 2+ can be separated by anion exchange resin. High bond ions can be eliminated by using 6 mol/L hydrochloric acid-ascorbic acid.Gallium remained in column can be eluted by 0.5 mol/L hydrochloric acid. In the presence of acidic and Titanium chloride, by means of benzene extracting,determined the ultraviolet-red complex combined GaCl - 4 with butylrhodamineB.The method has been applied to determination of micro amounts of Gallium in lead-zinc mineral satisfactorily.  相似文献   

7.
利用“416-A”回归最优设计研究Ca(NO3)2?4H2O、KNO3、NH4H2PO4、MgSO4?7H2O对水培白菜的产量效应。数学模拟建立了四种肥料与白菜产量的回归方程:y=97.808-4.337x1+3.445x2-2.690x3+8.299x4-6.894x1x2+17.331x1x3-7.389x1x4-3.191x2x3+6.364x2x4+0.063x3x4-9.629x12-17.150x22-17.915x32-24.066x42。经检验回归关系显著,并对回归系数进行了检验。从回归方程可得:MgSO4?7H2O对产量以直接作用为主,其次为Ca(NO3)2?4H2O、KNO3和NH4H2PO4。Ca(NO3)2?4H2O与其它三种肥料均有交互作用,其中与NH4H2PO4交互作用达极显著水平。从产量效应回归关系优选出配方浓度为:Ca(NO3)2?4H2O:971mg/L;KNO3:931mg/L;NH4H2PO4:204mg/L;MgSO4?7H2O:581mg/L。采用回归最优设计结合水培研究肥料效应精确可行。  相似文献   

8.
初步明确甜菜中铜的吸收特点、耐受性以及过量铜对甜菜的危害,为合理利用铜素肥料奠定基础,为研究甜菜重金属危害提供资料。以铜处理浓度:Cu2+ 0.31、5.0、50.0、100.0 μmol/L 的营养液为基质,培养甜菜幼苗,研究过量铜对甜菜影响。结果表明:(1)幼苗颜色随着Cu2+浓度的增加,逐渐由绿变黄,根、叶鲜重逐渐变小。(2)微量元素:根中铜、锌、锰、铁、硼、钼含量增加,锰先下降,后略增加。叶中铜、硼、钼含量增加,锌、锰先增加后下降,铁变化不明显。(3)大量元素:根中氮、磷、钙、镁增加,钾先增加后下降。叶中全氮、磷、钾、钙、镁呈增加趋势。氮元素在根叶中含量差异不明显,其它元素含量叶大于根。  相似文献   

9.
Influence of Transverse Flexural Crack on Chloride Penetration in Concrete   总被引:1,自引:0,他引:1  
The mechanism for chloride penetration in cracked concrete and its major impact factors were analyzed. As a result, a revised chloride diffusion model based on Fick's Law was built by dual porous medium model. Then several cracked reinforced concrete beams self-anchored with sustained flexural loads were immersed in the 5% NaCl solution with the condition of dry-wet cycles. After 15 times of dry-wet cycles, the rapid chloride testing (RCT) was used for the determination of chloride ion content of the powder at each cracked sections. The test results show that: 1) with the condition of dry-wet cycles, the chloride content will occur a peak in the surface 20mm concrete, so the depth for surface convection zone can be assumed to be 15~20 mm; 2) when the crack width is less than 0.3mm, the equivalent chloride diffusion coefficient increases steadily, which agrees well with model's prediction; when the crack width is larger than 0.3mm, the equivalent chloride diffusion coefficient augments rapidly and influence of convection on chloride penetration becomes more significant; 3) the deterioration factor for equivalent chloride diffusion coefficient in flexural cracked concrete is directly correlative with crack width, which can be expressed by second order power function or separate function.  相似文献   

10.
几种理化处理对秦岭冷杉种子萌发特性的影响   总被引:6,自引:3,他引:6  
李庆梅  孙玉玲 《种子》2007,26(4):41-44
采用流动水冲洗、赤霉酸(GA3)溶液浸种、硝酸钾(KNO3)溶液浸种、氧化氢(H2O2)溶液浸种等方法处理秦岭冷杉种子,对秦岭冷杉种子的萌发特性进行研究,进一步探讨秦岭冷杉种子快速解除休眠、促进萌发的技术。结果表明,流动水冲洗对秦岭冷杉种子萌发具有明显的促进作用;50mg/L、100mg/L、200mg/L赤霉素均可显著提高种子发芽率;硝酸钾对秦岭冷杉种子萌发有促进作用,0.1mol/L硝酸钾效果最好;1%过氧化氢对秦岭冷杉种子的萌发作用效果最佳。  相似文献   

11.
为保障猪肉产品卫生安全,探讨了电化水在猪肉加工灭菌中的应用效果、参数和作用机制。结果表明,电化水通过有效氯、O3、H2O2和氧化还原电位等多种因素协同灭菌,应用于猪肉加工冲淋环节的最佳参数为:有效氯浓度140.5 mg/L、O3浓度1.12 mg/L、H2O2浓度3.44 mg/L、pH 8.13和氧化还原电位(ORP)1 072.7 mV,冲淋时间16 s。该参数下对猪肉表面菌落总数、大肠菌群的杀灭对数值分别为1.89 lg(CFU/25 cm2)、1.33 lg(MPN/25 cm2),相对自来水分别提高1.43 lg(CFU/25 cm2)、0.88 lg(MPN/25 cm2),并保持4 h内持续抑菌;同样对器具的消毒效果显著优于次氯酸钠。  相似文献   

12.
Ca2+对低温下水稻幼苗膜的保护作用   总被引:45,自引:0,他引:45  
梁颖  王三根 《作物学报》2001,27(1):59-64
缺Ca2+的水稻幼苗在低温胁迫下(4℃36h),细胞膜功能及超微结构破坏严重。在培养液中加入适当浓度的Ca2+(0.5~1.0mmol/L)可降低冷胁迫下稻苗的电解质渗漏率和MDA含量,提高SOD、CAT、POD活性,保护叶绿体和线粒体超微结构免遭破坏。CaM特异性抑制剂CPZ能部分抑制Ca2+降低冷害稻苗的电解质渗漏率及MDA含量和提高SOD、POD活性  相似文献   

13.
红甜菜具有很高的营养价值和药用价值。硒元素是人体所必需的元素,被国内外医药界和营养学界尊称为“生命的火种”。为探究硒元素对红甜菜苗期各矿物质累积的影响,本研究以荷兰红甜菜品种‘必久’为研究材料,对其施用不同种类不同浓度的外源硒(0、0.5、5、10 mol/L)。根据试验结果得出以下试验结论:Na2SeO4和Na2SeO3在0.5 mol/L时,对红甜菜吸收Na、Mg、Ca、Mn、Fe影响不大;Na2SeO4和Na2SeO3在5 mol/L时均能够促进红甜菜对Na、Mg、Ca、Mn、Fe的吸收;Na2SeO4和Na2SeO3在10 mol/L时,除对Mg元素吸收起到抑制作用外,红甜菜吸收Na、Mg、Ca、Mn、Fe量均略高于对照,但吸收促进作用将会减弱。结论在红甜菜苗期施用适当浓度的外源硒会提高红甜菜苗期对Na、Mg、Ca、Mn、Fe的吸收。  相似文献   

14.
江富成  王希  杨柳  张习敏  乙引 《种子》2012,31(5):19-22
将无菌土人参种子接种在含0.001、0.01、0.1、1.0、10、30 mmol/L Ca2+的MS固体培养基中,光照恒温培养,测定种子发芽率、发芽时间,以及幼苗形态、生理指标。结果表明,当培养基Ca2+浓度为0.1 mmol/L时,种子萌发时间最短,平均叶片数最多,平均株高最高,分别为9 d、11.82片和4.28 cm;当培养基Ca2+浓度为1.0 mmol/L时,种子发芽率、Chl a含量、Chl b含量最高,依次为74%、1.00 mg/g和0.14 mg/g;当培养基Ca2+浓度为30 mmol/L时,水势急剧下降;随着培养基中Ca2+浓度的增加,土人参根系活力呈曾加趋势,培养基中的Ca2+浓度为1.0 mmol/L时,根系活力为1.67 mg/(g.h)。土人参生长的最佳钙离子浓度范围为0.01~1.0 mmol/L。  相似文献   

15.
水分胁迫下钙对大豆叶片光合作用的改善效应   总被引:21,自引:0,他引:21  
杨根平  高向阳 《作物学报》1995,21(6):711-716
本工作采用控制营养液中的钙量和叶片喷钙的方法来提高植株的钙水平,研究了钙对水分胁迫大豆光合作用的效应,结果表明:在水分胁迫下,经高钙处理(14mmol/L Ca^2+)大豆叶片保持高的光合速率;中钙(5mmol/L Ca^2+)处理次之;低钙(营养液中不加Ca(NO3)2,而以NaNO3代之)处理一周叶片光合作用速率最低,相对变化最大,在同样程度的水分胁迫下,高钙处理叶片具有较高的CO2羧化效率,  相似文献   

16.
Immersion in sodium chloride solution was adopted to periodically test chloride ion concentration at the surface of concrete and regression analysis was completed.And time dependent law of surface chloride ion concentration of concrete with time was investigated.Influences of sodium chloride solution concentration, water to cement ratio and fly ash content on size and accumulation rate of surface chloride ion concentration were also analyzed.It is found that surface chloride ion concentration gradually grows with the of time increase the of time and reaches a steady state finally.With the increase of sodium chloride solution concentration, surface chloride ion concentration reaches the steady state more quickly and then increases numerically.Bigger water to cement ratio means quicker accumulation of surface chloride ion concentration and greater surface chloride ion concentration.Fly ash replacement could fasten accumulation of surface chloride ion concentration and surface chloride ion concentration increases with the increase of fly ash content.An improved model was proposed by comparison and correction of current models.  相似文献   

17.
为了明确一氧化碳(CO)对桑黄菌丝的生长和三萜的累积作用。将CO供体氯高铁血红素添加到桑黄菌丝体系中,采用pH计、电导率仪、比色法、高效液相色谱等分析了pH值、电导率、过氧化氢(H2O2)、超氧化物阴离子、抗氧化物酶活性和三萜含量。研究发现,CO处理对桑黄菌丝培养液pH值的影响差异不显著。电导率、H2O2和超氧阴离子含量除30μmol/LCO处理增加外,其他CO浓度处理1~8d内基本呈降低趋势,与之相反,抗氧化物酶活性除30μmol/LCO处理降低外,其他CO浓度处理基本呈增加趋势。除30 μmol/LCO处理下三萜和白桦脂醇含量降低外,CO增加了三萜和白桦脂醇含量,其中10 μmol/LCO处理4d时三萜含量增幅最大,比同期对照增加了 29.63%;20 μmol/LCO处理1d时白桦脂醇含量增幅达最高值,比同期对照增加了30.96%。由此可见,低浓度CO处理对桑黄菌丝未造成胁迫伤害,其生物累积量未受到抑制,但其这种生物效应还需进一步多材料验证。  相似文献   

18.
The Influence on the Strength of Cement Mortars by Emulsified Epoxy   总被引:2,自引:0,他引:2  
The influence on the strength of cement mortars by adding emulsified epoxy is studied, and epoxy resin polymer cement mortars with excellent performances are made up through modifying ordinary Portland cement with emulsified epoxy and micro-fine slag. The microstructure of the epoxy resin polymer cement materials are studied and their action and mechanism are discussed by means of modern detection measures such as SEM, XRD. The experimental results indicate cement mortars modifying emulsified epoxy and micro-fine slag have higher compressive strength and flexible strength. The series effects of water-reducing, density, pozzolanicity, filling and solidification cross linking through the action together of epoxy organism and micro-fine slag can endow cement-based materials with perfect mechanic performance. The main hydration products in the system are C-S-H gel and micro-crystal hydrated calcium aluminate. When epoxy resin is solidified, the organism is network. No Ca(OH) 2 has been found.  相似文献   

19.
杨军 《粮食储藏》1997,26(4):35-37
文章提出用量气法测定粗蛋白含量,在PH=8-10的胡酸钠缓冲介质中,加入过量的次氯酸钙溶液与氨氮反应,量取氮气体积,方法快速,操作简便,分析结果与凯氏法一致。  相似文献   

20.
为研究β-环糊精(β-Cyclodextrin, β-CD)在农药高效利用和环境保护等领域中应用的可行性,本试验采用研磨法、超声波法和饱和水溶液法制备了β-CD与毒死蜱的包合物,并利用紫外光谱、差示热分析和红外光谱法分析验证了包合物的形成以及毒死蜱在β-CD溶液中的包结行为。结果表明饱和水溶液法的包合效果最佳,包合率达到45.8%;最佳条件为:投料比为1:1(摩尔比),恒温搅拌时间为3h,包合温度为60℃;验证结果表明反应形成了包合比为1:1的包合物,且稳定常数为K=33.33 L/mol,吉布斯函数△G =-8.69 KJ/mol;本试验证明了β-CD能够对毒死蜱产生包合作用,毒死蜱分子部分功能基团进入了β-CD空腔,并形成了稳定包合物。  相似文献   

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