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塑料吸水质量分数测定的能力验证研究
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作者 郑素萍 王从科 +3 位作者 李金鹿 张霞 凡丽梅 董方旭 《计量技术》 2017年第7期37-40,共4页
依据标准GB/T1034-2008、ISO62:2008、ASTMD570.98(Reapproved 2010)ε1的要求和CNAS(中国国家评定认可)规定的程序进行本次能力验证,目的用于评价参与实验室塑料吸水质量分数(吸水率)的能力。采用z比分数评价各参加实验室的... 依据标准GB/T1034-2008、ISO62:2008、ASTMD570.98(Reapproved 2010)ε1的要求和CNAS(中国国家评定认可)规定的程序进行本次能力验证,目的用于评价参与实验室塑料吸水质量分数(吸水率)的能力。采用z比分数评价各参加实验室的测试结果,各参加实验室结果的中位值作为测试样品吸水质量分数的指定值,以标准化四分位距(NIQR)作为变动性度量值(目标标准偏差)。通过该项目的研究,制备了均匀性、稳定性符合要求的能力验证样品,并采用适当的统计方法评估了参加实验室的塑料吸水质量分数的检测能力。 展开更多
关键词 塑料 吸水质量分数(率) 能力验证 技术分析与建议
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羧甲基纤维素钠凝胶的吸水性能研究
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作者 马艳梅 苗书颜 《化学试剂》 CAS 北大核心 2023年第10期77-82,共6页
以滤纸、氢氧化钠、一氯乙酸为原料,制备羧甲基纤维素钠,再加入含有Al 3+的交联试剂,即获得羧甲基纤维素钠凝胶。并探究最合适的交联试剂浓度,进而探究羧甲基纤维素钠凝胶的吸水及保水性能。利用单因素分析法探究pH和温度对羧甲基纤维... 以滤纸、氢氧化钠、一氯乙酸为原料,制备羧甲基纤维素钠,再加入含有Al 3+的交联试剂,即获得羧甲基纤维素钠凝胶。并探究最合适的交联试剂浓度,进而探究羧甲基纤维素钠凝胶的吸水及保水性能。利用单因素分析法探究pH和温度对羧甲基纤维素钠凝胶吸水性能的影响。结果表明:羧甲基纤维素钠凝胶在去离子水中的吸水性能及吸满水后的保水性能较好,交联试剂中Al^(3+)浓度为0.1 mol/L,温度为20℃,pH 5.00时,质量吸水倍率最大,为12.48。表明羧甲基纤维素钠凝胶具有一定的吸水性和保水性。 展开更多
关键词 羧甲基纤维素钠凝胶 性能 质量倍率 性能
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再生骨料透水混凝土毛细吸水性能研究 被引量:3
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作者 陈守开 符永淇文 +1 位作者 别亚静 刘新飞 《混凝土》 CAS 北大核心 2020年第12期147-150,154,共5页
以再生骨料透水混凝土(RAPC)毛细吸水性能为研究对象,分别以单粒级(9.5~19.0 mm),4种水灰比和双粒级(4.75~9.5、9.5~19.0 mm),5种级配(1∶1、1∶2、2∶1、2∶3、3∶2),水灰比0.3制备RAPC,分析其前8 d不同时段的毛细吸水质量和吸水高度... 以再生骨料透水混凝土(RAPC)毛细吸水性能为研究对象,分别以单粒级(9.5~19.0 mm),4种水灰比和双粒级(4.75~9.5、9.5~19.0 mm),5种级配(1∶1、1∶2、2∶1、2∶3、3∶2),水灰比0.3制备RAPC,分析其前8 d不同时段的毛细吸水质量和吸水高度变化规律,以此来反映RAPC毛细吸水特性。结果表明,RAPC毛细吸水质量和高度都呈幂函数形式变化,在0~6 h内增长速率较快,之后增长速率逐渐降低直至平稳,在单粒级水灰比0.3和双粒级2∶1级配下,毛细吸水质量及高度达到最大值。部分未完全水化的水泥熟料在RAPC毛细吸水的作用下进一步参加反应,在一定程度上可提高RAPC的强度和耐久性。 展开更多
关键词 再生骨料透混凝土 毛细吸水质量 毛细高度 灰比 级配
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基于核磁共振技术对水泥砂浆高温后孔隙结构及水分迁移特征的研究 被引量:2
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作者 何娅兰 宁麟 +1 位作者 李炀 钟秀杰 《硅酸盐通报》 CAS 北大核心 2023年第7期2336-2343,共8页
为研究高温后水泥砂浆内部水分迁移特征,将水泥砂浆试件300、400、500℃高温处理后表面镀蜡(留有一个上表面),随后将试件未镀蜡一端置于液面下2 cm进行自渗吸试验。采用核磁共振(NMR)技术T_(2)谱及核磁共振成像研究高温作用后水泥砂浆... 为研究高温后水泥砂浆内部水分迁移特征,将水泥砂浆试件300、400、500℃高温处理后表面镀蜡(留有一个上表面),随后将试件未镀蜡一端置于液面下2 cm进行自渗吸试验。采用核磁共振(NMR)技术T_(2)谱及核磁共振成像研究高温作用后水泥砂浆试件水分迁移情况及特征。结果表明,随着处理温度升高,试件胶凝孔和气孔或裂隙占比增大,而毛细孔占比逐渐降低,试件吸水质量减小,吸水质量前24 h内快速增加,随后减缓并趋于稳定。同时,高温作用影响毛细管吸水率,当处理温度小于等于400℃时,高温可增大毛细管吸水率;当处理温度大于400℃时,高温反而削弱毛细管吸水率。通过引入毛细吸收系数S来表征毛细管吸水率,S在6 h前大于10,而在6 h后减小超过2个数量级。另外,水分迁移存在优先孔径,在毛细孔中迁移的优先孔径为10~480 nm,在气孔或者裂隙中迁移的优先孔径为1680~16800 nm,且随浸水时间增加,水分更倾向由大孔传输到较小孔隙中。最后,通过核磁共振成像可实时观测到水分迁移位置由外到内,迁移速度与试件处理温度呈正相关。 展开更多
关键词 孔隙结构 分迁移 高温 吸水质量 毛细收系数 泥砂浆
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Impacts of Excessive Soaking on N, P, and K in Substrates Plots and Seedling Growth
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作者 王甲辰 左强 +4 位作者 谷佳林 肖强 邹国元 张琳 王美菊 《Agricultural Science & Technology》 CAS 2012年第1期158-161,180,共5页
[Objective] The aim was to study on impacts of excessive soaking N, P, and K insubstrate plots of and seedling growth. [Method] Substrate was designed to add additional 1/2 water after saturation and expansion. Dispos... [Objective] The aim was to study on impacts of excessive soaking N, P, and K insubstrate plots of and seedling growth. [Method] Substrate was designed to add additional 1/2 water after saturation and expansion. Disposable excessive soak- ing and regression relation of nutrition infusion of substrate plots were studied by design of 13 time gradient. Plant nutrition absorption and growth effects after sub- strate plots immersed by water were investigated by growing tomato. [Result] Con- centration and time of the three nutrition immersed in water had the regression equation of each, as follows: N=-2E-05t2+0.016 lt+2.0553, P=0.002 2t+2.248 5 and K=0.004 7t+0.875 8. With nutrition loss of the three, however, loss amount was al- most same with variance analysis of regression equation, which may result from its volatilization. Regression equations of P and K were: P=0.125 7t-0.117, and K=0.022 5t.1514, which led to adverse impact on plant absorption of N and K above ground, whose equations were N=20.64e-4E-0.4t, and K=E-06t2-0.011 3t+29.055. Meanwhile, un- der the condition, sound seedling index was not impacted a lot by excessive immer- sion. [Conclusion] This study has provided theoretical reference for guidance of sub- strate plot soaking method, cultivation and regulation, and breeding, as well as agri- cultural production. 展开更多
关键词 Substrate plot Saturation and expansion for absorption Excessive water Regression equation
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Stability Analysing of Unsaturated Soil Slope 被引量:1
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作者 张士林 邵龙潭 《Journal of China University of Mining and Technology》 2003年第1期55-59,共5页
The stability of unsaturated soil slope has been the hot point recently. Especially, the seeping rainfall makes losing stability of unsaturated soil slope, and causes enormous loss to the producation and safety of oth... The stability of unsaturated soil slope has been the hot point recently. Especially, the seeping rainfall makes losing stability of unsaturated soil slope, and causes enormous loss to the producation and safety of other people. The seeping rainfall makes volumetric water content of unsaturated soil slope changing, and the volumetric water content has directly relationship with matric suction. And matric suction also has directly relationship with the stability of unsaturated soil slope. So the change of matric suction influence the stability changing, that is, safety coefficient has decided relationship with volumetric water content. The profile of dangerous volumetric water content curves of unsaturated soil slope has been obtained. If a volumetric water content curve of some unsaturated soil slope belongs to one of these dongerous curves, the unsaturated soil slope could be in danger. So this is called DVWCCP(dangerous volumetric water content curves profile). By monitoring the volumetric water content curves can obtain the stability information of some soil slope to serve producing and safety. 展开更多
关键词 unsaturated soil stability analysis seeping rainfall volumetric water content matric suction DVWCCP
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Carbonaceous Adsorbents Prepared from Sewage Sludge and Its Application for Hg^0 Adsorption in Simulated Flue Gas 被引量:11
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作者 方平 岑超平 +1 位作者 陈定盛 唐志雄 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2010年第2期231-238,共8页
The carbonaceous adsorbent was prepared from mixtures of dewatered sludge and sawdust with enhanced ZnCl2 chemical activation.Characteristics of the adsorbent were studied using scanning electron microscope(SEM) ,Four... The carbonaceous adsorbent was prepared from mixtures of dewatered sludge and sawdust with enhanced ZnCl2 chemical activation.Characteristics of the adsorbent were studied using scanning electron microscope(SEM) ,Fourier transform infrared spectroscopy(FT-IR) ,and adsorption of nitrogen.The surface analysis showed that the carbonaceous adsorbent had good specific surface and porosity(394 m 2 ·g-1of BET surface,0.12 and 0.10 ml·g-1of microporous and mesoporous volume,respectively) .The oxygen functional groups such as OH,C O and C O were found on the surface by FTIR and XPS(X-ray photoelectron spectroscopy) .The adsorption of elemental mercury(Hg0) on the carbonaceous adsorbent was studied in a fixed bed reactor.The dynamic adsorption capacity of carbonaceous adsorbent increased with influent mercury concentration,from 23.6μg·g-1at 12.58μg·m-3to 87.9μg·g-1at 72.50μg·m-3,and decreased as the adsorption temperature increased,from 246 μg·g-1 at 25°C to 61.3μg·g-1 at 140°C,when dry nitrogen was used as the carrier gas.The carbonaceous adsorbent presented higher dynamic adsorption capacity than activated carbon,which was 81.2μg·g-1and 53.8μg·g-1respectively.The adsorption data were fitted to the Langmuir adsorption model.The physical and chemical adsorption were identified on the adsorbent. 展开更多
关键词 carbonaceous adsorbent dewatered sludge Hg0
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Water Quality Index and Absorption of Zinc from Electroplating Industry Effluent Using Fungi 被引量:1
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作者 M. R. Rajan M. Periyasamy K. Shanmugapriya 《Journal of Agricultural Science and Technology》 2011年第3期337-341,共5页
The present study deals with the Water Quality Index (WQI) and absorption of zinc from electroplating industry effluent using ftmgi. The physico-chemical parameters such as EC (Electrical Conductivity), TDS (Tota... The present study deals with the Water Quality Index (WQI) and absorption of zinc from electroplating industry effluent using ftmgi. The physico-chemical parameters such as EC (Electrical Conductivity), TDS (Total Dissolved Solids), total hardness, magnesium, calcium, chloride, sodium, potassium, nickel, chromium and zinc content was above the permissible limits of BIS (Bureau of Indian Standards). The WQI was 13, which showed that the pollution level of the electroplating industry effluent was severe in the rating scale and the effluent was not suitable for disposal without treatment. Three fungal species such as Aspergillus niger, Peinicillium chrysogenum and Rhizopus nigricans were used for absorption studies. Different concentrations (25, 50, 75 and 100%) of electroplating industry effluent along with 1 gm of fungal mycelium with (1%) and without carbon source was incubated in a shaker for a period of 7 days in order to observe zinc absorption capacity. The absorption capacity of zinc was found to be higher in Aspergillus niger followed by Rhizopus nigricans and Penicillium chrysogenum. Among the three fungal species Aspergillus niger had high (50%) potential of zinc absorption with carbon source and low concentration (25%) of electroplating industry effluent. 展开更多
关键词 Water Quality Index eleclroplating industry EFFLUENT ABSORPTION ZINC fungi.
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Firmness measurement of peach by impact force response 被引量:2
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作者 Yong-wei WANG Jun WANG Chong YAO Qiu-jun LU 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2009年第12期883-889,共7页
The impact force response of a peach impacting on a metal flat-surface was considered as nondestructive determination of firmness. The objectives were to analyze the effect of firmness, drop height, fruit mass, and im... The impact force response of a peach impacting on a metal flat-surface was considered as nondestructive determination of firmness. The objectives were to analyze the effect of firmness, drop height, fruit mass, and impact orientation on the impact force parameters, and to establish a relationship between the impact force parameter and firmness. The effect of fruit firmness, drop height and fruit mass on the impact force parameters (coefficient of restitution, percentage of energy absorbed, and coefficient of force-time) was evaluated. The study found that the coefficient of restitution, percentage of energy absorbed, and force-time impact coefficient were significantly affected by fruit ripeness, but not affected by drop height, impact position (fruit cheek), and mass. The percentage of absorbed energy increased with ripeness, while the force-time impact coefficient and coefficient of restitution decreased with ripeness. Relationships were obtained between the three impact characteristic parameters (force-time impact coefficient, coefficient of restitution, and percentage of energy absorbed) and peach firmness using a polynomial model (R2=0.932), S model (R2=0.910), and exponential model (R2=0.941), respectively. 展开更多
关键词 FIRMNESS PEACH Impact force Coefficient of restitution Percentage of absorbed energy
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