以改性松香为交联剂的盐酸川芎嗪分子印迹聚合物吸附性能研究

以盐酸川芎嗪为模板分子,丙烯酸为功能单体,改性松香(马来松香乙二醇丙烯酸酯)为交联剂,采用水溶液悬浮聚合法合成了具有松香骨架的盐酸川芎嗪分子印迹聚合物(MIP).研究了该MIP对盐酸川芎嗪的平衡吸附条件.利用高效液相色谱法对盐酸川芎嗪分子印迹聚合物特征吸附性及选择吸附性进行了研究.结果表明,该MIP对模板分子盐酸川芎嗪具有良好的特征吸附及选择吸附性能.为天然药物中分离富集纯化生物碱类活性成分川芎嗪提供了一种新型材料.     

两嵌段共聚高分子在固液界面吸附的Monte Carlo模拟(Ⅰ)——吸附链的构型分布

用MonteCarlo方法对两嵌段共聚高分子在固液界面的吸附进行模拟,获得了固液界面区吸附链节的分布和吸附构型大小分布等微观信息.考察了吸附性链节的吸附能ε_Aa和两嵌段共聚高分子中吸附性链节比例f对固液界面区高分子链节的分布和各种吸附构型大小的影响.结果表明,吸附层厚度主要由两嵌段共聚高分子中非吸附性链段的长度决定.     

两嵌段共聚高分子在固液界面吸附的Monte Carlo模拟（Ⅰ）— …

用Ｍｏｎｔｅ Ｃａｒｌｏ方法对两嵌段共聚高分子在固液界面的吸附进行模拟,获得了固液界面区吸附链节的分布和吸附构型大小分布等微观信息。考察了吸附性链节的吸附能εＡａ和两嵌段共聚高分子中吸附性链节比例ｆ对固液界面区高分子链节的分布和各种吸附构型大小的影响。结果表明,吸附层厚度主要由两嵌段共聚高分子中非吸附性链段的长度决定。     

空心球状碘氧化铋的制备及其对染料的吸附降解性能

通过溶剂热法制备出空心球状的碘氧化铋,采用X射线粉末衍射(XRD)、扫描电子显微镜(SEM)和物理吸附仪等技术手段对样品的结构和性能进行了表征。选用阳离子型染料罗丹明B和阴离子型染料活性蓝KN-R来研究BiOI的吸附性能和光催化活性。结果表明,在不同的溶液初始pH值下BiOI对不同结构和类型的染料表现出不同的吸附性和光催化降解性。BiOI对罗丹明B和活性蓝KN-R均有较高的吸附性和降解率,且光催化降解效率可以达到96.2%和92.5%。捕捉实验表明,h+在光催化降解中起主要作用。     

两嵌段共聚高分子在固液界面吸附的Monte Carlo模拟(Ⅱ)──界面浓度分布和吸附量

用MonteCarlo方法对两嵌段共聚高分子在固液界面的吸附进行模拟,获得了固液界面区总链节密度和吸附链节浓度分布、链附着率、表面覆盖率和吸附量等信息,考察了吸附性链节的对比吸附能 ε>_An 和两嵌段共聚高分子中吸附性链节比例f对它们的影响.结果表明,较大时,吸附量先随f的增加而上升,在f=0.4左右达到最大值后逐渐下降.     

聚丙烯-麦饭石功能纤维的性能

应用冷场发射扫描电镜(FE-SEM)、声速法、蠕变测试、苯胺吸附和振荡烧瓶法对聚丙烯-麦饭石功能纤维的形貌、取向因子、蠕变性、吸附性和抗茵率进行了测试与表征.研究表明:聚丙烯纤维和麦饭石添加剂呈镶嵌结构,聚丙烯-麦饭石功能纤维表面存在一些微细褶皱,其杨氏模量和取向因子相对较低,蠕变现象明显;苯胺的吸附率在30%左右;抗菌率在90%以上,而且水洗50次后抗茵率基本不变,具有很好的吸附和抑菌作用.     

负载二氧化锰球形吸附剂的制备及锂吸附性质的研究

将粉末状无机吸附剂MnO_2分散负载于交联聚丙烯酰胺,制成了球形吸附剂。以静态法和柱式法用LiOH(0.1mol/L),LiCl(0.1mol/L)混合溶液和实际盐湖卤水研究了吸附剂对Li~+的吸附性。对LiOH、LiCl等摩尔混合溶液和大柴旦湖水,锂吸附容量分别为5.90和3.40mmol/gMnO_2·HCl溶液(0.25mol/l)可将被吸附的锂近于完全洗脱,同时将吸附剂再生以重新使用。     

抗癌药长春新碱及其与微管蛋白相互作用的电化学研究

在 0 0 5mol/LTris,0 15mol/LNaCl溶液中 ,用吸附伏安法研究长春新碱 (VCR) ,其峰电位在 -1 68V (vs .Ag/AgCl) ,峰电流与 1 0× 10 -8～ 2 0× 10 -7mol/LVCR浓度成正比 ,检测限为 7 0× 10 -9mol/L .用常规脉冲极谱法、线性扫描和循环伏安法等研究该体系的电化学行为 .实验表明 ,电极还原过程为具有吸附特征的不可逆过程 .VCR的吸附符合Frumkin吸附等温式 .也研究了VCR与微管蛋白的相互作用 .实验表明 ,VCR与微管蛋白形成一电活性的结合物 ,这一结合物具有吸附性 ,且还原过程也为不可逆过程     

2.5次微分溶出出伏安法测定水中镍

应用平衡法测定了４种浓度＾１４Ｃ－苄嘧磺隆溶液在１０种土壤的吸附与解吸性能。结果表明；土壤对苄嘧磺隆有很强的吸附性，且随供试土壤理化性质的差异其吸附性呈现明显变化，安徽红壤和江西红壤性水稻土吸附率为７３．２４％和５０．９５％；江苏黄潮土Ｂ和Ａ吸附率分别为１０．７４％和２１．１２％。     

镍(Ⅱ)-硫代氨基脲体系的吸附伏安法研究

本文用计时电量法探讨了镍(Ⅱ)-硫代氨基脲在悬汞电极上吸附还原的机理,表明其吸附模式为直接吸附,吸附形体为Ni(T₃C)₂²⁺。利用Ni(TSC)₂²⁺络合物的吸附性,可采用预先将Ni(TSC)₂²⁺吸附富集在悬汞电极上然后再进行电位扫描的吸附伏安法来测定痕量Ni.线性扫描伏安法和微分脉冲伏安法的检测下限可分别达到1×10^-8mol/L和4×10^-9mol/L。     

Strategies for multi-site GLP studies

 A GLP study can be performed at more than one site. This is called a multi-site study. Although, the study is performed at different sites, it is still one study and must completely comply with the GLP principles. The fact that different activities are conducted at different sites implies that the planning, the organization and the communication are crucial for the success of the study. This means that all the staff involved should know their responsibilities and should have the knowledge and skills to realize all the phases of the study according to the GLP principles. To achieve a well managed multi-site study, several strategies for setting up such a study can be followed. This paper focuses on the responsibilities, communication, and collaboration of the personnel, which are involved in a multi-site study. Several case studies are highlighted, and we concluded that the basic communication triangle in a single-site GLP study between test facility management, study director, and the quality assurance unit should be extended to the communication among test facility and test site management, study director, principle investigator(s), and the quality assurance units at the test sites. Introduction Received: 14 August 2002 Accepted: 26 November 2002     

Geochemical Anomaly Characteristics of Cd in Soils around Abandoned Lime Mines: Evidence from Multiple Technical Methods

Lime mines are a potential source of pollution, and the surrounding soil environment is generally at threat, especially in abandoned lime mines. This paper focuses on the study area in eastern Anhui, attempting to analyze whether Cd enrichment is related to abandoned mines. On the basis of geological investigation, this study systematically used XRD, XRF, GTS and universal Kriging interpolation to determine the distribution law of Cd in the study area, and evaluated the potential ecological risk of Cd. The results showed that the main mineral types of soil samples of red clastic rock soil parent material (RdcPm) and soil samples of carbonate soil parent material (CPm) were not completely the same. Correlation analysis showed that CaO, MgO and Cd were positively correlated with the CPm. Human activities led to the accumulation of Cd in the study area. High Cd was mainly concentrated in the northwest of the study area, which was correlated with abandoned mines and soil parent materials. The study area was dominated by slight potential risks, although some areas had medium potential risks and high potential risks. All potential high risks were in the CPm field. This study provides a scientific basis for the comprehensive utilization and development planning of soil in the study area.     

Microfluidic chip for fast nucleic acid hybridization

The design and experimental verification of a fast nucleic acid hybridization microchip using the fluidic velocity and strain rate effects was conducted. This hybridization chip was able to increase the hybridization signal 6-fold, reduce non-specific target-probe binding and background noise within 30 min, as compared to conventional hybridization methods, which may take from 4 h to overnight. Excellent correlation between experimental results and simulation analysis was obtained in this study. A detailed study of a newly designed microfluidic chip for enhancing hybridization was conducted. Three different designs of devices were fabricated and tested. Two different lengths of targets, 25-mer oligonucleotide and 1.4 kb ssDNA, were tested in this study. The hybridization efficiency can be improved by introducing velocity and extensional strain rate to the sample. This study demonstrates that the signal in the proposed method exhibits intensities 6-fold higher than those in static conditions. The necessary time for the hybridization process can be reduced from overnight to 30 min using the methods developed in this study. Experimental results also show that the strain rate provides stronger effect on hybridization than that of velocity. Combining hybridization with microfluidic concepts of velocity and strain rate effects may provide additional specificity and efficiency in nucleic acid detection and genomic study. This microfluidic hybridization chip can provide potential application in genomic study.     

Perchlorate in water via US Environmental Protection Agency Method 331 Determination of method uncertainties, lowest concentration minimum reporting levels, and Hubaux-Vos detection limits in reagent water and simulated drinking water

US Environmental Protection Agency (EPA) Method 331 determines perchlorate in drinking water using non-suppressed ion chromatography with tandem mass spectrometry. This study reports the results of calibration and recovery studies in reagent water, as well as of a recovery study in simulated drinking water (i.e., total dissolved solids are 500 mg/mL each of chloride, sulfate, and bicarbonate). The perchlorate concentrations in the study ranged from 0.05 to 64 ng/mL. At 95% confidence, the Hubaux-Vos detection limit (H-V DL) was 0.04 ng/mL for the calibration study and the simulated-drinking-water recovery study, and 0.03 ng/mL for the reagent-water recovery study. The lowest concentration minimum reporting level was 0.03 ng/mL for reagent water and 0.0 7 ng/mL for simulated drinking water, again at 95% confidence.     

Determination of phytase activity in feed by a colorimetric enzymatic method: collaborative interlaboratory study.

Fourteen laboratories participated in a collaborative study (coded fyt9404) and 13 laboratories participated in a study (coded fyt9410) to validate a colorimetric assay for determination of microbial phytase activity in feed. For each study, all laboratories received 6 laboratory samples provided by one commercial supplier (phytase activity levels within the range of 200-400 per kg) to be analyzed in duplicate. Method performance was calculated and statistical calculations were executed according to AOAC guidelines. Results from 3 laboratories for study fyt9404 and from one laboratory for study fyt9410 were excluded from statistical analysis because of invalid data determined during initial review by Youden pair, value versus laboratory. For study fyt9404, repeatability relative standard deviation (RSDr) values ranged from 6.2 to 8.6%, and reproducibility relative standard deviation (RSDR) values ranged from 14.1 to 27.6%. No outliers were identified. For study fyt9410, RSDr values ranged from 3.9 to 7.9%, and RSDR values ranged from 14.0 to 20.5%. With outliers excluded, RSDr values ranged from 2.5 to 7.9%, and RSDR values ranged from 14.0 to 20.5%.     

Sequential changes of the cardiomyopathy in Duchenne muscular dystrophy by 201Tl myocardial SPECT

201Tl myocardial SPECT was performed to evaluate cardiomyopathy in Duchenne type of progressive muscular dystrophy (DMD). Follow up SPECT images of the same patients were also obtained about 1 year after the first scan. Cases subjected to study were 10 DMD. At the first study the hypoperfusion area of the left ventricular muscle was observed in 6 cases (60%) out of 10. At the second study the hypoperfusion areas became wider and lower in 4 out of 6 cases (66.7%). The new hypoperfusion area which was not demonstrated at the first study was observed at the second study in one case of these cases. These results suggested that the positive rate of cardiomyopathy in DMD by 201Tl myocardial SPECT was high, and 201Tl myocardial SPECT is a useful examination to detect the change of myocardial damage in DMD.     

Complementary use of inter-laboratory certification study data

The agreed purpose of an inter-laboratory certification study is to characterise a certified reference material (CRM). In addition to this, any (successful) certification study may also be utilised as a laboratory/method performance study by the participants. The intention of this note is to emphasise the complementary use of certification study data by the participants of the certification study and to explain the options involved. On this occasion, an apparent paradox arising in the interpretation of certification study data is resolved. The procedures for bias correction and estimation of bias-related uncertainty contributions discussed on this occasion are, however, generally applicable to normal CRM use. Received: 4 February 1999 / Revised: 16 July 1999 / Accepted: 21 July 1999     

假说在探究学习中的应用

探究学习是体现新课程理念的一种新的学习方式。而建立假说又是开展探究学习的核心环节。文中从4个方面简述了建立假说的方法,然后又列举了3种类型的案例,具体说明了假说在探究学习中的应用。     

Complementary use of inter-laboratory certification study data

The agreed purpose of an inter-laboratory certification study is to characterise a certified reference material (CRM). In addition to this, any (successful) certification study may also be utilised as a laboratory/method performance study by the participants. The intention of this note is to emphasise the complementary use of certification study data by the participants of the certification study and to explain the options involved. On this occasion, an apparent paradox arising in the interpretation of certification study data is resolved. The procedures for bias correction and estimation of bias-related uncertainty contributions discussed on this occasion are, however, generally applicable to normal CRM use. Received: 4 February 1999 / Revised: 16 July 1999 / Accepted: 21 July 1999     

Clinical evaluation of safety and human tolerance of electrical sensation induced by electric fields with non-invasive electrodes

This paper reports the first clinical safety study of human tolerance of electrical sensation using non-invasive, flexible surface-type electrodes and exponentially decaying electric pulses. The study evaluated the effect of electric fields in the absence of a drug and an anesthetic, and was performed in light of potential applications in the field of erectile dysfunction (ED). Twenty impotent patients who had previously received injection or intraurethral therapies were enrolled in the study. Voltage escalations from 50 to 80 V (in 10-V increments) with a single pulse of 3-ms duration were performed with meander-type electrodes placed on the shaft and part of the glans of the penis. The electric fields-induced sensation was assessed via a pain scale from 0 to 10. All 20 patients, who were free to withdraw from the study at any point, completed the voltage escalation study. No clinical safety concerns were apparent and no skin irritation was observed after electric treatment. Our initial study indicates that the pulses in the tested voltage range were well tolerated by most patients. In previous animal experiments under analogous experimental conditions, the application of 50 V has been found effective for transdermal drug delivery into the penis.