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1.
为改善蒙脱土对Pb(Ⅱ)的吸附性能,以碳酸钙作为致孔剂,以钠基蒙脱土(MMT,montmorillonite)作为实验原料,制备多孔蒙脱土材料(PM,porous montmorillonite)。通过(SEM,scanning electronmicroscopy),(FTIR,fourier transform infrared spectrum),(XRD,X-ray diffraction)进行表征分析,研究了PM对Pb(Ⅱ)的吸附性能。实验结果表明:PM具有发达的孔状结构;在25℃时,PM对Pb(Ⅱ)的吸附量,随pH值的增加先增加后减小,在pH为5.5时达到最大;PM对Pb(Ⅱ)的吸附动力学过程符合准二级动力学模型;吸附等温线符合Langmuir模型,在25℃,pH为5.5时,饱和吸附量达到143.5mg·g。  相似文献   

2.
Two kinds of Ru(II)-bipyridine complexes,cis-di(thiocyanate)bis(2,2′-bipyridyl-4,4′-dicarboxylate) ruthenium(II) andcis-di(thiocyanate)bis(2, 2′-bipyridyl-3, 3′-dicarboxylate) ruthenium(II), were utilized as the sensitizers to the nanocrystalline TiO2 film electrodes. Study shows that the two dyes have quite different sensitization properties due to the strong steric effect of carboxyl groups. In addition, the pretreatment to nanocrystalline TiO2 film electrodes with TiCl4 was investigated, which is an effective way to improve the photoelectric conversion performances of sensitized TiO2 electrodes.  相似文献   

3.
以1-(2-噻唑偶氮)-2-萘酚(TAN)螯合物,于Shim-pack CLC-CN柱上,用含甲醇-四氢呋喃-醋酸-醋酸钠缓冲液(pH=3.5)-乙醇(60:19.8:19.8:0.4 V/V)溶液作流动相,并用分光光度检测器于570nm处进行检测,发展了一种高效液相色谱分离测定铜(Ⅱ),镍(Ⅱ),钴(Ⅱ)的方法.此法具有高的灵敏度,其绝对检测限分别为:铜(Ⅱ)1.8ng,镍(Ⅱ)1.8ng和钴(Ⅱ)0.6ng.在测定条件下,大多数金属离子不干扰.  相似文献   

4.
以2—巯基吡啶为配体的钴(Ⅱ)、锰(Ⅱ)二种螯合物.经EDTA络合滴定分析、热重分析、红外光谱分析,确认了螯合物的组成与结构.结果表明:配体2—巯基吡啶是以S,N两原子为配体原子,与Mn(Ⅱ)以2:1、与Co(Ⅱ)以3:1的配比形成中性螯合物。  相似文献   

5.
Configurations of three η2 models of transition-metal [60]fullerene derivatives C60M(CO)5(M=Cr, Mo and W) have been optimized at B3LYP/LanL2DZ level. On the basis of the optimized geometrical structures, their electronic spectra and the frequency dependence of third-order nonlinear optical polarizabilities γ in different optical processes of third-harmonic generation (THG), electric-field-induced second-harmonic generation (EFISHG) and degenerate four-wave mixing (DFWM) are calculated by using TDB3LYP model based on LanL2DZ level coupled with the SOS (sum-over-state) method. The obtained results show that their electronic spectra have a red shift compared with that of [60]fullerene and different transition-metal functional groups added to C60 cage may result in different spectrum properties. For the three studied species, (η^2-C60)Mo(CO)5 has the largest third-order nonlinear optical polarizability.  相似文献   

6.
The biological behavior of fullerene derivatives shows their considerable potential application in medicine field. To understand the biodistribution of C60 derivatives as drugs or drug carriers, a simple water-soluble derivative C60(OH)x(O)y was labeled with99mTc. A γ-counter and a single photo emission computed tomography (SPECT) were used to assess the biodistribution and metabolism of the labeled compound in mice and rabbits, respectively. The results showed that the compound could be absorbed rapidly by tissues, especially by coronal bone, breastbone, backbone, extremity honeycomb, liver and spleen. The clearance was slow from all tissues except for brain. The compound might be excreted through urine and enteron. The biodistribution shows some difference from that of Yamago et al. In this note, we discuss the possible reason leading to the difference. Further study is needed to find out to what extent the C60 itself determines the biodistribution of derivatives.  相似文献   

7.
通过多种方法“醋酸铬(II)水合物的制备”实验进行探究,分析比较得出最适合学生实验的方法。  相似文献   

8.
The light-oxidation degradation processes of Zn(dmid)(phen)2(dmid = 4, 5-dimercapto-1,3-dithiole-2 one, phen = 1,10-phenanthroaline) in pyridine solvent has been monitored, h has been found under the light, dmid^2- of Zn(dmid)(phen)2 in pyridine solution could generate NCS^- and NCS^-replaces dmid^2- to form Zn(NCS)2 (phen)2 simultaneously. The crystal structure of Zn(NCS)2 (phen)2 has been determined. In the crystal of Zn(NCS)2 (phen)2. two NCS^- ligands are arranged in syn-configuration, and there is strong π-π interaction between the two adjacent parallel phen.  相似文献   

9.
合成出硝酸镍与二乙烯三胺(dien)的新的配位化合物,并分析讨论该配合物的晶体结构。  相似文献   

10.
通过对MRPⅡ工作原理及其基于集成功能的特点分析,探讨了以MRPⅡ为核心集现代管理技术,计算机与网络技术和生产工艺于一体具有先进管理思想和方法的计算机集成制造系统CIMS的集成原理,并以国家863/CIMS示范应用工程YH-CIMS为实例,分析了CIMS环境下MRPⅡ与DCS的信息集成原理。  相似文献   

11.
研究了茶渣对Ni(Ⅱ)的吸附性能。分别考察了吸附时间、茶渣投加量、Ni(Ⅱ初始浓度、茶渣粒径、温度、pH值等因素对茶渣吸附Ni(Ⅱ)的影响。在吸附时间1 h、茶渣投加量1.2 g、Ni(Ⅱ)初始浓度200 mg/L、茶渣粒径60目、pH值11.2情况下,吸附率可达81%。表明了茶渣对Ni(Ⅱ)有较好的吸附性能。  相似文献   

12.
0 IntroductionThbiep ycroidmipnlee)xru ctahteinoinu mof(Ⅱ r)u t(he Rniuu(mbip,y m)3ai2n +ly) atrnids- t(r2is -,(21’ -,10-phenanthroline)ruthenium(Ⅱ) (Ru(phen)32 +) ,is a kindof sensitive analytical reagent for electrogenerated chemilumi-nescence(ECL) and chemiluminescence(CL) ,on which a par-ticular review has been presented[1]. The earliest publicationon the synthesis of Ru(bipy)32 +appeared in 1936[2], andduringthefollowing30 years ,theinvestigations relatedtothissubstance were only in…  相似文献   

13.
采用第一性原理的经过库仑力修正的密度泛函方法,研究了CeO_2(111)表面不同氧空穴附近形成的不同的活性O_2物种.在此基础上,研究这些O_2物种对Au原子的吸附能力,得到过氧O_2-2对Au吸附能为1.8eV,吸附较强;超氧O-2对Au的吸附能为0.4eV,吸附较弱.研究结果为Au/CeO_2催化CO氧化提供了重要理论思路.  相似文献   

14.
在pH=8.51的硼砂——硼酸缓冲体系、CPB为表面活性剂的条件下,Zn(Ⅱ)与邻硝基苯基荧光酮(0-NPF)形成1:4的紫红色络合物,最大吸收波长为550nm,灵敏度(ε)为1.25×105L.mol-1.cm-1.络合物在常温下能稳24小时以上,含锌量在0~20μg/50ml范围内符合比耳定律.在掩蔽剂存在下,有较好的选择性,测定大米、人发中锌的含量,结果令人满意.  相似文献   

15.
A new absorbent of nanometer-size TiO2 colloid for Cu(Ⅱ) was studied in this work. The adsorption rate could reach above 99% when the pH values were at the range of 5-6. The adsorption balance time, adsorption capacities, and the eluent were investigated. A novel method of trace Cu(Ⅱ) preconcentration and separation with nanometer-size titanium dioxide colloid and determination by flame atomic absorption spectrometry (FAAS) was advanced. The detection limit (3σ) of the method was 1.15 μg· L~(-1) , and the relative standard deviation (R.S.D) was 1.53% (n=6). Environmental sample experiments were also conducted to test the feasibility of the method, and it came out that the recovery rates were between 95.9% and 97.8%.  相似文献   

16.
用振动样品磁强计并结合X射线衍射准确判定了Nd2.4Er0.6Fe27.31Ti1.69化合物的磁晶各向异性方式, 研究结果发现, Nd2.4Er0.6Fe27.31Ti1.69化合物的磁晶各向异性从室温时的易面转变到低温时的易锥.  相似文献   

17.
An electrochemical method for the simultaneous determination of lead(II) and Cadmium(II) with a calix[6]arene modified carbon paste electrode (CPE) has been developed. Pb2+ and Cd2+ were accumulated at the surface of the modified electrode via formation of chemical complexes with calix[6]arene, and reduced at 1.40 V. During the following anodic potential sweep, reduced lead and cadmium were oxidized, and two well-defined striping peaks appeared at about −0.60 V and −0.84 V. Compared with a bare carbon paste electrode, the calix[6]arene modified CPE greatly improves the sensitivity of determining lead and cadmium. The stripping peak currents change linearly with the concentration of Pb2+ 3.0×10−8–8.0×10−6 mol·L−1 and with that of Cd2+ 6.0×10−8–1.0×10−5 mol ·L−1. The detection limits of Pb2+ and Cd2+ are found to be 8.0×10−9 mol·L−1 and 2.0×10−8 mol·L−1, respectively. The modified carbon paste electrode was applied to determine trace levels of lead and cadmium in water samples. Comparing with that of atomic absorption spectrometry, the results suggests that the calix[6]arene modified CPE has great potential for the practical sample analysis. Foundation item: Supported by the National Natural Science Foundation of China (60171023) Biography: JI Xiao-bo (1980-), male, Master, research direction: electroanalytical chemistry.  相似文献   

18.
氨基膦酸树脂对汞、铅混合液的吸附研究   总被引:3,自引:1,他引:3  
研究氨基膦酸树脂对汞、铅混合溶液的吸附行为.结果表明:树脂对混合溶液中的汞、铅都能产生吸附;当混合溶液中汞、铅浓度相同时,树脂对铅的吸附率要大于树脂对汞的吸附率;当混合液中汞、铅浓度不相同时,在实验条件下,无论是汞的浓度大于铅的浓度,还是铅的浓度大于汞的浓度,其吸附率都是树脂对铅的吸附率大于树脂对汞的吸附率;当树脂的功能基与溶液中汞、铅离子的物质的量相当时,树脂能基本完全吸附溶液中的汞、铅离子.所以,氨基膦酸树脂可作为含汞、铅废水的实用吸附剂.  相似文献   

19.
Molecular modeling of cyanoacrylates and ureas with D1 protein ofPisum sativum have been presented. Studies show that these two kinds of inhibitors occupy the similar region in the D1 protein. Cyanoacrylates have more bii aites than ureas, thus they have higher activities.  相似文献   

20.
催化褪色光度法测定痕量锰(II)   总被引:1,自引:0,他引:1       下载免费PDF全文
研究在酸性介质中及活化剂氨三乙酸存在条件下,锰(Ⅱ)对高碘酸钾氧化酸性品红褪色的反应具有显著的催化作用,利用此性质,建立了测定痕量锰(Ⅱ)的新体系.确定了反应条件及共存离子的影响,方法的灵敏度为5.24×10-11gMn/mL,锰(Ⅱ)的浓度在0.20~19.9ng/mL范围内,△A与Mn(Ⅱ)含量呈良好的线性关系.该法用于池塘水及面粉中锰的测定,获得了满意的结果.  相似文献   

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