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1.
Two homologous series of mesogenic materials which incorporate a 1,4-tetrafluorophenylene moiety and a terminal cyano- or nitro-substituent have been synthesized by using palladiumcatalysed coupling procedures. The compounds exhibit nematic and/or smectic A phases.  相似文献   
2.
The goal of this study was to investigate the effect of photothermal laser irradiation on rat breast tumor (DMBA-4) vascular contents. An 805-nm diode laser was used in our experiment with a power density ranging from 0.32 to 1.27 W/cm2. The dynamic changes of oxygenated hemoglobin and total hemoglobin concentrations, delta[HbO2] and delta[Hb]total, in rat tumors during photothermal irradiation were noninvasively monitored by a near-infrared spectroscopy system. A multichannel thermal detection system was also used simultaneously to record temperatures at different locations within the tumors. Our experimental results showed that: (1) photoirradiation did have the ability to induce hyperthermic effects inside the rat breast tumors in a single exponential trend; (2) the significant changes (P < 0.005) of delta[HbO2] and delta[Hb]total in response to a low dosage of laser irradiation (0.32 W/cm2) have a single exponential increasing trend, similar to that seen in the tumor interior temperature; and (3) the increase in magnitude of delta[HbO2] is nearly two times greater than that of delta[Hb]total, suggesting that photoirradiation may enhance tumor vascular oxygenation. The last observation may be important to reveal the hidden mechanism of photoirradiation on tumors, leading to improvement of tumor treatment efficiency.  相似文献   
3.
大孔吸附树脂处理含磺胺废水的研究   总被引:8,自引:0,他引:8  
利用大孔吸附树脂处理含磺胺废水。实验表明,DRHⅢ树脂对磺胺具有良好的吸附-解吸效果。原废水中磺胺浓度约为17.2g/L,COD约为13750mg/L,经树脂吸附处理后,废水中COD去除率约86%,磺胺的吸附率88.2%,树脂的解吸率为97.5%,磺胺的回收率约86.0%,其纯度达99.8%。在废水有效处理的同时实现了废物资源化,具有良好的环境效益和较高的经济效益。  相似文献   
4.
A nanocomposite photocatalyst composed of AlFeO3 and TiO2 is prepared, and characterized through X-ray diffraction. Application of the nanocomposite for the photodegradations of eosin dye and methyl orange gives an improved photoactivity compared with TiO2-only nanomaterials. The optimal concentration of AlFeO3 in the composite is about 1.0 wt% under UV excitation, and 9.0 wt% under sunlight excitation for the improved photoactivity. Furthermore, this nanocomposite is more active for eosin photodegradation if natural sunlight rather than UV is used. This may be due to the reason that adding AlFeO3 nanoparticles into TiO2 matrix can promote the separation of photogener-ated charge carriers, and extend the photoresponse of TiO2 toward visible region, which results in an increase in the solar energy utilization efficiency.  相似文献   
5.
Monitoring fluctuations in enzyme overexpression facilitates early tumor detection and excision. An AIEgen probe (DQM‐ALP) for the imaging of alkaline phosphatase (ALP) activity was synthesized. The probe consists of a quinoline‐malononitrile (QM) core decorated with hydrophilic phosphate groups as ALP‐recognition units. The rapid liberation of DQM‐OH aggregates in the presence of ALP resulted in aggregation‐induced fluorescence. The up‐regulation of ALP expression in tumor cells was imaged using DQM‐ALP. The probe permeated into 3D cervical and liver tumor spheroids for imaging spatially heterogeneous ALP activity with high spatial resolution on a two‐photon microscopy platform, providing the fluorescence‐guided recognition of sub‐millimeter tumorigenesis. DQM‐ALP enabled differentiation between tumor and normal tissue ex vivo and in vivo, suggesting that the probe may serve as a powerful tool to assist surgeons during tumor resection.  相似文献   
6.
IntroductionThecomprehensivemathematicalmodeldevelopedinthefirstpartofthispaper[1]containsdozensofcoupledequationsthatformalargenonlinearequationsystem.Herewecombineanalyticalandnumericalmethodstosolveitanddiscussandanalyzesomeimportantproblemsinmicroc…  相似文献   
7.
通过恒电流法和失重法研究了加入La对Al-Sn-Bi阳极电化学性能的影响,对比分析了阳极的电化学溶解特征。结果表明:不同含量La对Al-Sn-Bi牺牲阳极的电位影响较小;电流效率比未加La的阳极有不同程度的提高,其中Al-Sn-Bi-0.1La的电流效率增幅较大;La可改善阳极的腐蚀形貌,使得表面溶解均匀,同时降低阳极腐蚀速率,提高其耐蚀性,其中含量0.1%La效果明显。  相似文献   
8.
9.
The aim of this study was to investigate the correlation between levels of a marker of oxidative DNA damage, 8-hydroxy-2′-deoxyguanosine (8-OHdG), in human saliva and urine, and to explore its potential application in fast diagnosis of many diseases (especially cancer) associated with oxidative damage. A simple and time-efficient method, based on capillary electrophoresis with electrochemical detection, was developed for the determination of salivary and urinary 8-OHdG. Under the optimum conditions, 8-OHdG and its coexisting analytes could be well separated within 16 min at a voltage of 14 kV in 60 mmol L?1 borax running buffer (pH 8.2). A good linear relationship was established between peak current and concentration of analytes over three orders of magnitude with detection limits (S/N = 3) ranging from 0.41 × 10?7 to 2.50 × 10?7 mol L?1 for all analytes.  相似文献   
10.
Cui D  Li Y  Lian M  Yang F  Meng Q 《The Analyst》2011,136(15):3149-3156
A simple and stability-indicating reverse phase high performance liquid chromatographic (RP-HPLC) method was developed and validated for the determination of olanzapine (OLN) and related impurities in bulk drugs. Eight impurities were characterized respectively, and particularly a new process impurity from OLN synthesis was structurally confirmed as 1-(5-methylthionphen-2-yl)-1H-benzimidazol-2(3H)-one (Imp-7) by X-ray single crystal diffraction, MS, (1)H NMR, (13)C NMR and HSQC. A mechanism of formation pathway for Imp-7 was proposed. Optimum separation for OLN and eight related impurities was carried out on an Agilent Octyldecyl silica column (TC-C(18), 4.6 mm × 250 mm, 5 μm) using a gradient HPLC method. The method was validated with respect to specificity, linearity, accuracy, precision, LOD and LOQ. Regression analysis showed good correlation (r(2) > 0.9985) between the investigated component concentrations and their peak areas within the test ranges for OLN and eight impurities. The repeatability and intermediate precision, expressed as RSD, were less than 1.74%. The proposed stability-indicating method was suitable for routine quality control and drug analysis of OLN in bulk drugs.  相似文献   
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