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221.
The matrix isolation technique with Fourier transform infrared detection has been applied to determine the products of gaseous radical reactions. The gas phase reactions were carried out in a discharge flow system and about 1% of the gas mixture was deposited onto a low temperature target through a pinhole. A differential pumping scheme was employed to maintain the pressure of the cryosystem below 10?5 torr while that of the flow system was kept at about 2 torr. Species including HO2 (from the H+O2 reaction), ClO2 (from the Cl+O2 reaction) and ClO (from the Cl+O3 reaction) have been produced in the gas phase and were successfully trapped in matrices and detected with an FTIR spectrometer. In addition, both HCl and HOCl have been detected as the reaction products from the gaseous ClO+HO3 reaction. The production of HCl from the ClO+HO2 reaction may have a significant impact on catalytic ozone destruction in the atmosphere.  相似文献   
222.
《Analytical letters》2012,45(14):2491-2501
Abstract

Fluorescence spectroscopy was applied to the development of a sensitive and simple method for the determination of chlorpromazine HCl and thioridazine-HCl. The method is based upon development of an intense fluorescence using N-bromosuccinimide as the fluorogenic reagent. The produced fluorescence has very characteristic excitation and emission spectra and was stable for at least one hour. The results were reproducible and as little as 5 ng/ml chloropromazine HCl and 1 ng/ml thioridazine-HCl could be determined. The method was applied successfully to the analysis of various commercially available dosage forms. The obtained results were in good agreement with those of the official BP 93 procedures.  相似文献   
223.
城市生活垃圾焚烧体系化学热力学平衡分析   总被引:19,自引:5,他引:19  
采用化学热力学平衡分析方法,分析城市生活垃圾焚烧体系污染物的排放特性。主要计算了聚氯乙烯(PVC)及典型城市垃圾焚烧过程氯元素的化学平衡组成及其浓度,同时研究了脱氯剂对PVC及垃圾中氯转化的影响。计算结果表明,PVC热态反应的主要产物是HCl气体,在加入脱氯剂后温度低于600℃时,脱氯剂对HCl的脱除作用很明显;城市生活垃圾热解和燃烧过程中在温度超过600 ℃,垃圾中的有机氯和无机氯都将转化为HCl气体,而此时脱氯剂失去效果。由计算结果得到控制HCl生成,消除二口恶英污染物的生成反应工艺条件。  相似文献   
224.
Three new Cu(II) supramolecular complexes [Cu(L1)Cl2]·2DMF (1), [Cu(L2)Cl2] (2) and [Cu(L3)Cl2]·DMF (3) (L1 = 3,3′-bis(2-benzimidazolyl)-2,2′-dipyridine, L2 = 3,3′- bis(N-ethyl-2-benzimidazolyl)-2,2′-dipyridine and L3 = 3,3′-bis(N-benzyl-2-benzimidazolyl)-2,2′-dipyridine) have been prepared and characterized by elemental analysis, IR spectra and single crystal X-ray diffraction. X-ray structural analysis of L1, L2·3.5H2O and L3·H2O indicates that all three ligands adopt the trans conformation with the two benzimidazole fragments located on opposite sides of the dipyridyl backbone. While in complexes 13, all the ligands display the cis conformation and behave as bidentate chelating reagents to coordinate with Cu(II). The inorganic chloride ions always act as a reliable hydrogen bonded acceptor in these structures, and the resulting C–HCl2Cu supramolecular synthons play a significant role in the formation and stabilization of the structures. Moreover, additional non-covalent interactions, such as C–Hπ, are also identified to extend the discrete (0-D) or low-dimensional (1-D) motifs into high-dimensional architectures.  相似文献   
225.
An efficient, photocatalytic chlorination of alkylarene α‐H groups using NaCl/HCl as a chlorine source has been developed, which involves a radical mechanism under visible‐light (including sunlight) conditions. A chlorine radical is proposed to be formed by an electron transfer from chloride ion to O2 in air through the bandgap hole of the semiconductor AgCl. The chlorination protocol is characterized by its use of natural sunlight or other visible light, mild conditions, cheap source of chlorine, green solvent, and high selectivity. The yield of benzylchloride is 95 % with a toluene conversion as high as 40 %, which rivals traditional chlorination methods.  相似文献   
226.
The accurate determination of prilocaine HCl levels in plasma is important in both clinical and pharmacological/toxicological studies. Prilocaine HCl is quickly hydrolyzed to o-toluidine, causing methemoglobinemia. For this, the present work describes the methodology and validation of a GC-MS assay for determination of prilocaine HCl with lidocaine HCl as internal standard in plasma. The validation parameters of linearity, precision, accuracy, recovery, specificity, limit of detection and limit of quantification were studied. The range of quantification for the GC-MS was 20-250 ng/mL in plasma. Within-day and between-day precision, expressed as the relative standard deviation (RSD) were less than 6.0%, and accuracy (relative error) was better than 9.0% (n = 6). The analytical recovery of prilocaine HCl and IS from plasma has averaged 94.79 and 96.8%, respectively. LOQ and LOD values for plasma were found to be 20 and 10 ng/mL, respectively. The GC-MS method can be used for determination from plasma of prilocaine HCl in routine measurement as well as in pharmacokinetic studies for clinical use.  相似文献   
227.
A potentiometric sensor modified with a nanocomposite of montmorillonite sheets decorated with polyaniline nanofibers (MT-PANI-NFs) as an efficient electroactive material and tricresyl phosphate (TCP) as a solvent mediator has been developed for the estimation of clomipramine HCl (CLP.HCl). The optimum potentiometric performance of the sensor was achieved by mixing of MT-PANI-NFs : TCP : graphene with a ratio of 2.69 : 30.11 : 67.20 (% wt/wt). The sensor exhibited a Nernstian slope of 59.0±0.1 mV decade−1 over the concentration range of 1.0×10−5−1.0×10−2 mol L−1 with a theoretically calculated detection limit of 5.0×10−6 mol L−1. The sensor performance was scrutinized in terms of several factors including thermal stability, pH effect, response time and selectivity. As, it displayed a high thermal stability at various temperature degrees (10–60 °C) with pH independency in the range of 3.5–8.5. Additionally, the developed sensor exhibited a very rapid performance for CLP.HCl detection with a fast response time of 4 s and reflecting a superior selectivity towards CLP.HCl over the other interfering species. SEM (scanning electron microscope) was used as a characteristic tool for the investigation of the proposed graphene sensor surface. Furthermore, the graphene sensor has been efficiently used for CLP.HCl estimation in its pharmaceutical formulations.  相似文献   
228.
建立了一种高效液卡甘色谱法同时测定禽肉中土霉素、四环素、金霉素、强力霉素残留的分析方法、禽肉样品用0.1mol/L Nac EDTA—Mollvaine缓冲溶液提取,清液用Oasis HLB固卡甘萃取柱和Carboxylic acid阴离子交换柱净化,用流动卡甘洗脱定容后,用紫外检测器于350nm,测定一在5~100μg/kg添加水平、回收率为60%~100%,相对标准偏差在16%以内土霉素、四环素的检出限为2μg/kg,金霉素、强力霉素的检出限为5μg/kg。  相似文献   
229.
<正>A membrane composed of an alginate(ALG) layer and a chitosan(CHS) layer with sustained antimicrobial efficacy was prepared.Ciprofloxacin HC1(CIP) was incorporated into the ALG layer.Morphological feature of the composite membrane was analyzed by scanning electron microscopy(SEM).Water uptake capacity,in vitro drug release,and in vitro antimicrobial activity were evaluated.The composite membrane exhibited perfect binding characteristic between the two layers.The water uptake capacity of all the membranes was above 800%.The CIP could release from the composite membranes for 48 h.The membrane could control the bacterial growth persistently.The results suggested that this CHS/ALG composite membrane incorporated with CIP had the potential for wound dressing application.  相似文献   
230.
The formation and growth of a self-organized zirconia porous layer can be achieved directly by anodization of Zr in chloride containing electrolytes. The morphology of the porous layers is affected by electrochemical conditions such as Cl concentration. Zirconia nanotubes with diameters ranging from 250 to 300 nm and a length of 33 μm were formed under proper conditions. The nanotubes have smooth and straight walls. The composition of the nanotubes was characterized by using an energy dispersive spectrometer. Selected area electron diffraction investigation reveals that the as-anodized zirconia nanotubes have an amorphous structure. Crystal phase transition and structural stability of the ZrO2 nanotubes after heat treatment were characterized. A possible growth mechanism is presented.  相似文献   
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