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偕胺肟树脂的吸铀机理  [PDF]
郑邦锭,蔡水源,庄明江,蒋龙生
华东政法大学学报 , 1985,
Abstract: 通过对偕胺肟树脂对铀的吸附等温线和吸附速率测定,研究了偕胺肟树脂在海水中的吸铀机理,实验表明树脂吸铀量随温度上升而增加,亦随pH值不同而变,由热力学计算的吸附焓变为ΔH=42.4千焦尔/摩尔,由动力学计算的吸附表观活化能为41.2千焦尔/摩尔,结果表明吸附过程是通过树脂的偕胺肟基对铀酰离子的化学吸附,而树脂对铀酰离子吸附能力的次序为:UO22+>[UO2(OH)3]->[UO2(CO3)3]4-。
玻璃钛吸附剂的研制及其吸铀性能研究  [PDF]
夏福兴,吴欣然,邱怀德,韩建成
海洋科学 , 1993,
Abstract: 本文报道一种机械强度高、吸铀性能较好的玻璃钛吸附剂的研制及吸铀性能研究。室内通水吸附剂回收率达99.4%,优于湿法制备的强度较好的水合氧化钛吸附剂。在铀浓度为lμg/ml时,铀的回收率平均为74.7%。铀在玻璃钛上的吸附是个吸热过程,吸附等温线显示两个平台,属分级交换模式。X射线衍射分析表明玻璃钛主要为无定形成分。
含偕胺肟基和羧基纤维状吸附剂的研制及其吸铀作用  [PDF]
傅文通,骆炳坤,陈连志,陈慧贞,庄万金,刘石玉
华东政法大学学报 , 1986,
Abstract: 在聚丙烯腈纤维上导入偕胺肟基和羧基,制得具有高吸铀量和高吸铀速度的纤维状吸附剂,每克纤维10天能从天然海水中吸铀4.6毫克,研究了纤维吸附剂的平衡吸铀量Xm和吸铀速度常数K与基团含量的关系,发现Xm和K分别与偕胺肟基和羧基含量相关,因而得出结论:偕胺肟基为吸铀活性基团,羧基为加快吸铀速度的促进基团,同时研究了纤维对铀的吸附机理,用分子轨函观点讨论吸附态的螯合结构.
蜂窝状活性炭对VOCs的吸-脱附性能研究  [PDF]
韩忠娟,罗福坤,李泽清
环境科学 , 2011,
Abstract: 蜂窝状活性炭适于处理大风量、低浓度有机废气,通过建立动态吸-脱附实验装置,系统研究了不同吸附质、入口甲苯浓度、空床气速、脱附温度等参数对其吸-脱附性能的影响.结果表明,在规定出口甲苯浓度时,降低入口甲苯浓度,蜂窝状活性炭可持续吸附时间增加,吸附效率提高;在工程应用吸附过程中,空床气速推荐取1.2~1.8m·s-1.在脱附过程中,出口甲苯浓度均出现峰值,随着脱附温度升高,曲线波动越大,工程应用中推荐脱附温度90℃;脱附空床气速对出口甲苯浓度峰值有影响,推荐取0.2~0.4m·s-1.
聚乙烯醇钛纤维含钛量和处理条件与吸铀值的试验  [PDF]
纺织学报 , 1992,
Abstract: 本文介绍了以聚乙烯醇粒子、凝固纤维、拉伸纤维、热处理纤维及维纶长丝,经钛液处理后制成的聚乙烯醇钛纤维吸取海水中铀的试验情况。文中阐述了钛液配方,不同制备条件和方法对吸铀值及含钛量的影响。
采用吸宫和电凝方法建立小鼠子宫内膜损伤模型的比较  [PDF]
王晏鹏(),黄琼晓,徐盛,舒静,()
- , 2017, DOI: 10.3785/j.issn.1008-9292.2017.04.11
Abstract: 目的:比较吸宫和电凝两种方法造成小鼠子宫内膜损伤模型的特点。方法:吸宫组采用自制20 G针头插入ICR小鼠一侧宫腔,以0.05 MPa负压全面吸宫1周;电凝组采用自制单极电针以0.5 W功率迅速电凝损伤子宫腔。均以对侧子宫为对照,对照仅插入针头或电针后退出。比较平均手术时间、术后单层子宫内膜厚度、妊娠4 d子宫内膜容受性相关因子的表达情况、妊娠10 d胎鼠数差别。其中HE染色观察子宫内膜组织形态学改变,蛋白质印迹法检测子宫内膜白血病抑制因子和抑瘤素M的表达。结果:吸宫组平均手术时间(10.2±1.3)min,电凝组平均手术时间(10.1±1.5)min,差异无统计学意义(P>0.05)。吸宫组损伤侧宫腔无封闭现象,电凝组有2只小鼠存在宫腔局部封闭、远段积水。损伤侧子宫内膜厚度吸宫组(96.1±13.2)μm,电凝组(88.9±16.8)μm,均比对照侧子宫减小(均P<0.01)。损伤侧子宫内膜白血病抑制因子和抑瘤素M的表达吸宫组高于电凝组,但两组损伤侧表达均低于对照侧(均P<0.01)。吸宫组损伤侧平均胎鼠数目(4.2±0.9)只,电凝组损伤侧平均胎鼠数目(3.9±1.7)只,均较对照侧下降(均P<0.01)。电凝组损伤侧还可见胎鼠死亡现象。结论:吸宫和电凝均可造成小鼠子宫内膜损伤,导致子宫内膜容受性下降和生育力受损。电凝损伤更符合重度宫腔粘连特征,而吸宫损伤可能更适用于轻中度宫腔粘连研究。
Abstract: Objective: To establish mouse endometrial injury model by curettage or coagulation. Methods: Female ICR mice were randomly allocated into 2 groups: in curettage group, a blunt 20G needle was inserted in one uterine horn with 0.05 megapascals negative pressure; in coagulation group, one uterine horn was coagulated using a monopolar electric needle with 0.5 watts power. In both groups the contra-lateral uterine horn was used as control. The morphological changes and thickness of endometrium were evaluated 1 week after operation. The endometrial samples were taken on d4 of pregnancy, and the expressions of endometrial receptivity-related cytokines were examined. The number of implanted embryos on each side of uterus was calculated on d10 of pregnancy. Results: There was no difference in operation time between 2 groups. In both groups, the endometrial glands and stroma were significantly reduced, and the endometrial thickness was also significantly decreased on injury side compared to contra-lateral horn. However, local injury was more severe in coagulation group, uterine obliteration and hydrops were developed in 2 mice of coagulation group, and none in curettage group. The expressions of leukemia inhibitory factor (LIF) and oncostatin M (OSM) were significantly reduced on injured side in both groups compared to opposite side; however, the expression of LIF and OSM in curettage group was higher than that in coagulation group. The numbers of implanted embryos were decreased in both groups on injured side compared to opposite side, and fetal death was only observed in coagulation group. Conclusion: Both curettage and coagulation can make injury on mouse endometrium, impair endometrial receptivity and reduce fertility. Curettage can cause moderate injury, and coagulation may lead to more severe injury. Key words: Electrocoagulation Abortion, induced/methods Uterine diseases Adhesions Endometrium Embryo implantation Disease models,
气吸与机械辅助附种结合式玉米精量排种器  [PDF]
杨丽,史嵩,崔涛,张东兴,高娜娜
农业机械学报 , 2012, DOI: 10.6041/j.issn.1000-1298.2012.S0.010
Abstract: 针对气吸式排种器播种玉米时漏播率较高、地头漏播严重等问题,设计了一种采用机械托种盘辅助附种的气吸式玉米精量排种器,利用托种盘窝眼对种子的托附和夹持作用,实现对气吸式排种盘的辅助附种。分析并确定了排种器工作区域和托种盘主要结构等关键参数。试验结果表明:在前进速度6~12km/h时,该排种器的粒距合格指数A≥91.40%、重播指数D≤3.82%、漏播指数M≤4.78%、合格粒距变异系数C≤18.37%,具有良好的排种效果。在10km/h作业速度下,该排种器(真空室相对压力-3kPa)的各项性能指标均明显优于常规气吸式排种器(真空室相对压力-4kPa),其中漏播指数比后者相对降低了29%。
Fe/HCl体系中缓蚀剂吸脱附诱导的电流/电位振荡  [PDF]
江俊伟,汪的华,甘复兴
腐蚀科学与防护技术 , 2002,
Abstract: 研究了HCl介质中活性电位区有机缓蚀剂在Fe电极表面吸脱附诱导产生的电化学振荡现象,及缓蚀剂浓度、电极电位和溶液搅拌等因素对振荡行为的影响。结果表明,在HCl介质中Fe电极的活性电位区同样得到了规整的电流振荡波,但相同条件下的振荡行为要弱于H2SO4介质中,随缓蚀剂浓度升高,振荡波的周期变长,振荡减弱;由阴极到阳极,电流振荡波形不同,周期也有所增长,搅拌对电流振荡无明显影响,同时报道了该缓蚀体系中恒电流电位振荡的新现象。
AHP树脂水相成型及吸铀机理的探讨  [PDF]
蔡水源,庄明江,郑文庆
华东政法大学学报 , 1981,
Abstract: 应用有机吸附剂从海水中提取铀,资料上已有若干报道.Davies.R.J,等曾经报道过用甲醛、间苯二酚胂酸缩合的树脂,虽然这种树脂交换容量大(通水112天,1010微克铀/克),选择性好,提取率高,但它在水中缓慢水解,吸附能力下降,溶损也较大(2.3%初量/周),因而没有得到进一步的发展.Bayer,E.提出用聚乙二醛三氨基苯酚和经硅藻土烧结的聚丙烯氧肟酸树脂,从海水中提取铀和铜等金属,但吸附量不很高,树脂的强度也差,因此很快就中断了研究.苏联一些学者也报道了用AH、等阴离子交换树脂提取铀的研究工作.AH-2Φ树脂具有一定的吸附量(30微克铀/克),在海水中比较稳定,但交换容量很低,价格也较贵.
炔氧甲基胺氨基三甲撑膦酸盐的缓蚀作用和阳极吸脱附行为研究  [PDF]
杜天保,曹殿珍,陈家坚,曹楚南
电化学 , 1996,
Abstract: 采用稳态极化曲线和交流阻抗测试技术研究了环己基二炔氧甲基胺氨基三甲撑膦酸盐在盐酸介质中的缓蚀作用机理和阳极吸脱附行为。对极化曲线实验数据按弱极化曲线模式进行拟合。研究结果表明,环己基二炔氧甲基胺膦酸盐在盐酸介质中的缓蚀机理为覆盖效应。吸附等温式符合Freundlich等温式。随缓蚀剂的脱附,阻抗谱在低频区出现感抗弧,且随脱附的进行而增大。
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