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101.
程琼  彭国治 《分析化学》1998,26(11):1315-1319
报道了一种抗真菌治疗新药酮康唑的吸附行为及其测定。该药物在玻碳电极上预富集后,用示差脉冲伏安法测定,其响应电流与药物浓度在2.0×10^-10-1.0×10^--5mol/L范围内呈线性关系;检屈限为4.0×10^-11mol/L。可用于尿和血清样品中药物含量的测定。  相似文献   
102.
Green light emitting Zn2SiO4:Mn phosphors have been prepared via a low-temperature solid-state reaction using mesoporous silica SBA-15 template. This mesoporous silica template method features low-temperature formation of phosphors and easy doping. The structure and morphology of the phosphors were characterized by XRD, SEM, TEM, and N2 adsorption/desorption techniques, which confirmed the single crystallinity, ordered mesostructure, closed pore channels, and elongated ropelike morphology. The luminescent properties were examined by photoluminescence spectroscopy at room temperature, and the results of fluorescence decay time measurements show non-single-exponential decay behavior and a decrease of the decay time with an increase of the Mn concentration.  相似文献   
103.
104.
Zhang YX  Li H  Havel J 《Talanta》2005,65(4):853-860
The prediction of migration time of electroosmotic flow (EOF) marker was achieved by applying artificial neural networks (ANN) model based on principal component analysis (PCA) and standard normal distribution simulation to the input variables. The voltage of performance, the temperature in the capillary, the pH and the ionic strength of background electrolytes (BGE) were applied as the input variables to ANN. The range of the performance voltage studied was from 15 to 27 kV, and that of the temperature in the capillary was from 20 to 30 °C. For the pH values studied, the range was from 5.15 to 8.04. The range of the ionic strength investigated in this paper was from 0.040 to 0.097. The prediction abilities of ANN with different pre-processing procedure to the input variables were compared. Under the same performance conditions, the average prediction error of the migration time of the EOF marker was 5.46% with RSD = 1.76% according to 10 parallel runs of the optimized ANN structure by the proposed approach, and that of the 10 parallel predictions of the optimal ANN structure for the different performance conditions was 12.95% with RSD = 2.29% according to the proposed approach. The study showed that the proposed method could give better predicted results than other approaches discussed.  相似文献   
105.
The reaction of 1,3-dipropyn-2-yloxycalix[4]arene with mercury(II)acetate could give mercury-containing alkynyl calixarenepolymer.The extraction behavior of 1,3-dipropyn-2-yl-oxycalix[4]arene towards mercury(II)ion was examined.When the moleratio of Hg~(2 )/calixarene was 1:1,the extractive percent can reach to 99.1%,and the extraction capacity was up to 431 mg/g.It couldalso decrease the Hg~(2 )concentration from 5 to 0.85 mg/L,which was only 17%of the national standard of effluent and satisfied thenational standard of drinking water.The extraction process included chemical reaction.  相似文献   
106.
采用共沉淀并加法制备了B位掺杂烧绿石型稀土复合氧化物纳米微晶Y2Sn2-xFexO7-δ(x=00~10)。制备的纳米微晶属于立方晶系,Fd3m,晶胞参数与掺杂量呈线性关系。通过Msbauer、TGDTA,气相色谱和γ射线辐照等技术研究了纳米微晶对CO的催化选择性能。结果表明,纳米微晶对CO的催化选择性明显高于一般粉料对CO的选择性;纳米微晶对CO的选择性与掺杂量有关;未辐照的纳米微晶,当掺杂量x=06时,其对CO的选择性为最高,辐照后的纳米微晶,当掺杂量x=04时,其对CO的选择性为最高  相似文献   
107.
The chiral separation of simendan enantiomers using capillary electrophoresis was studied with beta-cyclodextrin (beta-CD) as chiral selector. The influences of the concentration and pH of borate buffer solution, beta-CD concentration and methanol content in the background electrolyte were investigated. These factors were compared with those in an HPLC with beta-CD as chiral mobile phase additive (CMPA-HPLC). The quantification properties of the developed CE method were examined. A baseline separation of simendan enantiomers was achieved in the background electrolyte of 20 mmol/L borate buffer (pH 11.0) containing 12 mmol/L beta-CD-methanol (50:50 in volume ratio). The CE method is comparable with CMPA-HPLC in chiral resolution, although the optimal pH in CE (11.0) is much higher than that (6.0) in CMPA-HPLC. This chiral CE method is applicable to the quantitative ananlysis and enantiomeric excess value determination of L-simendan.  相似文献   
108.
Self‐healing hydrogel such as polyacrylic acid (PAA) hydrogel has attracted increasing attention based on its promising potential applications. However, it usually suffers from low strength especially as mechanical device. Herein, a commercial microcrystalline cellulose (MCC) was modified with acrylamide to graft polyacrylamide (PAM) chains on the particle surface. The acrylamide‐modified MCC (AM‐MCC) was then dispersed in monomer solution of acrylic acid to prepare composite hydrogel. The mechanical properties of the obtained composite hydrogels and the self‐healed hydrogels were carefully measured by compressive and tensile tests, and by dynamic mechanical analysis. Our results demonstrate that introduction of a small amount of AM‐MCC such as 3 wt% can not only reinforce the original hydrogel and the healed hydrogel markedly, but also improve self‐healing efficiency obviously. The analyses indicate that in addition to the reversible multi‐interactions such as hydrogen bonding and ionic interactions, the entanglements between the PAA chains of the hydrogel matrix and the PAM chains grafted on the MCC particles have also played an important role on the improvement in mechanical performances and the healing ability of the hydrogel. Moreover, the responsiveness to exterior ion has been tested to indicate potential application of the composite hydrogel as self‐healable sensor.  相似文献   
109.
We report on a photoluminescence observation of robust excitonic polarons due to resonant coupling of exciton and longitudinal optical (LO) phonon as well as Fano-type interference in high quality ZnO crystal. At low enough temperatures, resonant coupling of excitons and LO phonons leads to not only traditional Stokes lines (SLs) but also up to second-order anti-Stokes lines (ASLs) besides the zero-phonon line (ZPL). The SLs and ASLs are found to be not mirror symmetric with respect to the ZPL, strongly suggesting that they are from different coupling states of exciton and phonons. Besides these spectral features showing the quasiparticle properties of exciton-phonon coupling system, the first-order SL is found to exhibit characteristic Fano lineshape, caused by quantum interference between the LO components of excitonic polarons and the continuous phonon bath. These findings lead to a new insight into fundamental effects of exciton-phonon interactions.  相似文献   
110.
Wang XS  Zhao H  Qu ZR  Ye Q  Zhang J  Xiong RG  You XZ  Fun HK 《Inorganic chemistry》2003,42(19):5786-5788
The reaction of Cu(I)(CH(3)CN)(4)BF(4) with 4-pyridylacrylic acid (4-HPYA) affords an unprecedented 8-fold interpenetrating diamondoid-like coordination polymer network [Cu(I)(3)(4-PYA)(2)(H(2)O)(BF(4)) ] (1) with a Cu(+)(4)(CO(2))(4) cluster as connecting node. The interpenetration in metal coordination polymers is the highest degree ever found within diamondoid nets containing a cluster as connecting note. Its fluorescent property was also reported.  相似文献   
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