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1.
以单分散的苯乙烯-甲基丙烯酸甲酯共聚物(P(St-co-MMA))微球为载体,FeSO4·7H2O和FeCl3·6H2O为铁源,NaOH为沉淀剂,在氧化石墨烯(GO)存在下,利用反相共沉淀法通过原位复合技术在P(St-co-MMA)微球表面包覆磁性氧化石墨烯(P(St-co-MMA)/Fe3O4/GO)。通过扫描电子显微镜(SEM)、透射电子显微镜(TEM)、傅里叶变换红外光谱仪(FT-IR)、X射线衍射仪(XRD)、振动样品磁强计(VSM)和氮吸附-脱附等温线对P(St-co-MMA)/Fe3O4/GO样品的结构和性能进行表征分析。研究结果表明:纳米级的磁性氧化石墨烯成功地负载在了微米级的共聚物P(St-co-MMA)表面,所制备的P(St-co-MMA)/Fe3O4/GO微纳米复合物平均孔径为14.55 nm,孔体积为0.204 2 cm3/g,比表面积为56.14 m2/g。该复合物具有超顺磁性和良好的磁响应性,能够满足磁分离的要求。  相似文献   

2.
将中空纤维膜反应器和芬顿试剂结合脱除烟气中的Hg0。研究了不同参数以及SO2、NO和O2等杂质气体对Hg0脱除的影响。结果表明:随着H2O2浓度、Fe2+浓度、溶液初始pH和温度的增加,Hg0脱除率先增加后降低,其最佳工作条件是H2O2浓度为6 mmol/L,Fe2+浓度为9 mmol/L,溶液初始pH为2.5,温度为20℃;增大液气比和通过减小气相流量增大停留时间均对Hg0脱除有增强作用,当液气比超过0.11时,Hg0的脱除率不再增加;当气相流量为0.6 L/min时,Hg0脱除率超过85%;SO2、NO对Hg0的脱除有抑制作用,O2对Hg0的脱除几乎没有影响;还测定出温度20℃下中空纤维膜反应器的比相界面积a=270.29 m-1和传质动力学参数kL=8.13×10-4 m/s,kG=0.786×10-6 mol/(m2·s·Pa)。  相似文献   

3.
韩蕊  李蔚  汪霖  严嵩 《医学教育探索》2017,43(6):800-805
采用无压烧结工艺制备了Nb2O5掺杂SrTiO3陶瓷,研究了Nb2O5掺杂量对SrTiO3陶瓷相组成、显微结构和微波介电损耗的影响。结果表明:Nb2O5掺杂对SrTiO3陶瓷的相结构没有产生明显的影响,但会在一定程度上阻碍样品的致密化,同时促进晶粒的生长。随着Nb2O5掺杂量的增加,SrTiO3陶瓷的介电常数从296逐渐下降至230左右,温度系数从1.714×10-3-1逐渐下降至1.629×10-3-1,Q×f值则先急剧升高,之后又慢慢下降。当Nb2O5掺杂量为0.15%(质量分数,下同)时,SrTiO3陶瓷样品的介电损耗最低,Q×f可达6 281 GHz,大约是纯SrTiO3(1 145 GHz)陶瓷样品的5.5倍(此时介电常数约为270,温度系数约为1.684×10-3-1)。此外,对材料显微结构、介电常数、温度系数特别是介电损耗变化的原因进行了分析。  相似文献   

4.
以铋硅酸盐玻璃(SiO2-Bi2O3-BaF2-AlPO4)为基质,通过掺杂Ho3+、Tm3+、Yb3+稀土离子,制备激光波长为2 μm的光纤激光器。对玻璃的声子能量、物理和光学性能进行了研究,确定基质配方为50SiO2-40Bi2O3-5BaF2-5AlPO4(SBBA,其中化学式前的系数为对应物质的摩尔分数,下同)。在玻璃基质中分别掺杂0.5Ho2O3-2.0Yb2O3(HY)、0.5Ho2O3-0.5Tm2O3-2.0Yb2O3(0.5HTY)及0.75Ho2O3-0.75Tm2O3-3.0Yb2O3(0.75HTY),研究了980 nm激发波长下样品的吸收、发射光谱和Judd-Oflet理论光谱参数。研究发现SBBA-0.75HTY中Ho3+的吸收截面、发射截面(σem)、FWHM(半峰宽)×σem数值最大,分别为7.38×10-21、10.54×10-21 cm2和19.71×10-26 cm3。掺入Tm2O3改善了玻璃激光器性能,且当Yb3+/Tm3+/Ho3+物质的量之比一定时,增加稀土离子含量,可加强红外发光及增益效果。  相似文献   

5.
研究了柠檬酸(CA)螯合Fe2+活化过碳酸盐体系中投加盐酸羟胺(HAH)对三氯乙烯(TCE)的去除效果。结果发现,HAH能有效将Fe3+还原为Fe2+,强化TCE的去除效果。当TCE初始浓度为0.15 mmol/L时,nSPCnFe2+nTCE=5:3:1时,在CA浓度为0.5 mmol/L条件下,HAH最佳投加浓度为1.5 mmol/L,此时TCE去除率为99.6%。·OH对TCE降解的贡献度为79.2%,O2-·的贡献度为21.9%。HAH可减轻HCO3-对TCE降解的抑制效应,中间产物为甲酸、NO2-和NO3-。HAH利于SPC/Fe2+/CA体系降解TCE,该结果可为实际TCE污染地下水修复提供技术支撑。  相似文献   

6.
[目的] 系统研究参麦注射液体外抗氧化性能。[方法] 采用铁还原抗氧化能力 (FRAP)法、1,1-二苯基-2-三硝基苯肼(DPPH)自由基清除法、一氧化氮(NO)自由基清除法、过氧化氢(H2O2)清除法、亚铁(Fe2+)离子螯合法分别测试不同稀释倍率参麦注射液的总抗氧化能力、DPPH·清除活性、NO·清除活性、H2O2清除活性和Fe2+离子螯合活性,并将结果与0.1mg/mL 2,6-二叔丁基对甲酚(BHT)、10 mmol/L水溶性维生素E(Trolox)和10%柠檬酸的结果进行比较。[结果] 参麦注射液具有一定的体外抗氧化能力,总抗氧化能力和对自由基清除活性均呈浓度正依赖性;10倍稀释参麦注射液总抗氧化能力显著低于BHT和Trolox (P<0.01),但高于柠檬酸(P<0.01);参麦注射液对不同自由基清除能力存在差异,其强弱顺序为:NO·[(54.4±6.6)%] > Fe2+离子螯[(42.6±3.2)%] > DPPH·[(36.2±2.8)%] > H2O2[(23.5±1.2)%]。[结论] 参麦注射液体外抗氧化活性研究将为其抗氧化药理学机制提供了实验依据。  相似文献   

7.
刘柳  程庆  樊菲  张斌  陈彧 《医学教育探索》2016,29(2):163-171,181
利用Suzuki偶联反应合成了3 种侧链含有不同电子受体的可溶性D-A型聚咔唑衍生物:聚[(9-(2-己基葵基)-9H-咔唑)-(9-(4-硝基苯基)-9H-咔唑)](PCz-NO2)、聚[(9-(2-己基葵基)-9H-咔唑)-(4-(9H-咔唑-9-基)苯甲醛)](PCz-CHO)和聚[(9-(2-己基葵基)-9H-咔唑)-(4-(9H-咔唑-9-基)苯甲腈)](PCz-CN)。基于这3种聚合物的存储器件(器件结构:Al(200 nm)/高分子(90 nm)/氧化铟锡(ITO)均表现出典型的电双稳电子开关效应和非易失性一次写入多次读出(WORM)型存储性能。随着共轭聚合物光学带隙的增加[2.26 eV(PCz-NO2)→2.79 eV(PCz-CHO)→3.20 eV(PCz-CN)],相应器件的启动阈值电压逐渐增大(-1.70 V→-1.81 V→-1.89 V);而电流开关比(ON/OFF)则依次减小(6.63×104→4.08×104→5.68×103)。含氰基的聚咔唑衍生物需要的开启电压最大,展现出来的电流开关比在3种聚合物中则最小。  相似文献   

8.
通过还原4,7-二溴-2,1,3-苯并噻二唑制备2,5-二溴邻苯二胺,并分别与1,10-邻菲罗啉-5,6-二酮、苊醌、菲醌和联苯甲酰缩合反应,制备了4种单喹喔啉衍生物(M1、M2、M3、M4)。在二乙酸钯(Pd(CH3COO)2)和配体三环己基膦的催化下,通过Suzuki反应将2,7-二(4,4,5,5-四甲基-1,3,2-二氧杂硼酸烷)-9,9-二辛基芴(M5)分别与M1、M2、M3、M4交替共聚制得4种聚合物(P1、P2、P3、P4)。通过FT-IR和1H-NMR等测试方法表征所有单体及聚合物的结构。通过UV-Vis光谱和荧光光谱探讨了4种聚合物在CHCl3溶液中本征态的光谱性能,以及相应聚合物的CHCl3溶液被低浓度三氟乙酸(TFA)质子化时的光学性能。结果显示,4种聚合物对低浓度TFA有良好的敏感性。聚合物P1与2.17×10-7 mol/L的TFA作用时,P1的CHCl3溶液明显变色。聚合物P2~P4的CHCl3溶液与4.32×10-3 mol/L的TFA作用时,溶液颜色发生变化,与此同时在UV-Vis光谱上500~800 nm处出现新的吸收带。同时,4种交替共聚物的CHCl3溶液具有较好的荧光性能,当溶液中加入低浓度的TFA时,即在4种聚合物的CHCl3溶液中分别加入7.0×10-10、1.73×10-6、7.5×10-7 mol/L和4.0×10-6 mol/L的TFA时,其荧光发射强度明显减弱。  相似文献   

9.
青蒿素分子印迹聚合物分子识别性研究   总被引:1,自引:0,他引:1  
目的 合成对青蒿素具有特异识别能力的分子印迹聚合物。方法 采用分子印迹技术合成了以青蒿素为模板分子,丙烯酰胺为功能单体,乙二醇二甲基丙烯酸酯为交联剂的青蒿素分子印迹聚合物。运用平衡结合试验研究了聚合物的吸附特性和选择识别能力。结果 Scatchard模型分析表明,该分子印迹聚合物在识别青蒿素分子的过程中存在两类不同的结合位点。高亲和力结合位点的离解常数Kd1=1.87 mmol/L ,最大表观结合常数QMAX1=27.99 μmol/g;低亲和力结合位点的离解常数Kd2=48.5 mmol/L,最大表观结合常数QMAX2=334.4 μmol/g。结论 结合底物的实验结果表明,青蒿素分子印迹聚合物对青蒿素具有良好的特征吸附和选择识别性能,为天然产物中高效分离纯化活性成分青蒿素提供了一种新型材料。  相似文献   

10.
为了提高天然黄酮类化合物槲皮素的水溶性,将天然高分子材料壳聚糖进行两亲性衍生化制成N-(4-咪唑甲基)-羟乙基壳聚糖(MHC),作为槲皮素自组装聚合物胶束载体,并采用1H NMR、元素分析法、芘荧光光谱法等进行了表征;同时采用单因素考察法进行了MHC-槲皮素胶束的工艺优化。结果表明,载体浓度为0.67%、槲皮素与MHC质量比为1∶10时可以获得粒径为(99.21±1.71)nm,Zeta电位为+(20.01±0.72)mV,载药量为(5.42±0.32)%的聚合物胶束;其体外释药曲线符合Higuchi方程Q=0.110 1t1/2-0.064。槲皮素胶束和槲皮素溶液剂静脉注射给药后,在大鼠体内平均滞留时间分别是21.42和0.30 h,AUC0-t分别为57.49和2.50 μg·h/mL,表明采用MHC为载体材料的槲皮素自组装胶束具有较好的增溶、缓释以及提高生物利用度的作用,可作为槲皮素等抗肿瘤药物的载体。  相似文献   

11.
Objective: To evaluatel the value of D-dimers in patients with acute aortic dissection (AAD). Methods: This study consisted of 16 patients with AAD and 27 non-AAD patients. Serum D-dimets were measured by Sta-Liatest D-DI immunoturbidimetric assay. Results: D-dimer level was higher (P < 0.001) in patients with AAD(7.91 ± 5.52 μg/ml) than that in non- AAD group(1.57±1.24 μg/ml). D-dimer was positive (>0.4 μg/ml) in all patients with AAD and in 10 control group patients (37%). Among patients with acute AAD, D-dimers tended to be higher in Stanford A than in Stanford B (8.67 ± 4.31 μg/ml vs. 3.24±1.27 μg/ml, P <0.01). D-dimer values tended to be higher in more extended disease(3.84 ± 1.65 μg/ml, 8.57 ± 3.58 μg/ml and 11.87 ± 5.69 μg/ml in thoracic aorta, thoracic and abdominal aorta, thoracic and abdominal aorta and iliacal arteries, respectively, P < 0.05 for both 8.57 ± 3.58 and 11.87 ± 5.69 vs. 3.84 ± 1.65 ). Including the control group into the analysis, we found a sensitivity of 100%, a negative predictive value of 100%, and a specificity of 66% and a positive predictive value of 64% for D-dimer in diagnosis of AAD in our patients with suspected AAD. Conclusion: D-dimer was elevated in patients with AAD. A negative D-dimer test result could be useful in excluding AAD.  相似文献   

12.
Objective: To set up a simple and reliable rat model of combined liver-kidney transplantation. Methods: SD rats served as both donors and recipients. 4℃ sodium lactate Ringer's was infused from portal veins to donated livers,and from abdominal aorta to donated kidneys, respectively. Anastomosis of the portal vein and the inferior vena cava (IVC) inferior to the right kidney between the graft and the recipient was performed by a double cuff method, then the superior hepatic vena cava with suture. A patch of donated renal artery was anastomosed to the recipient abdominal aorta. The urethra and bile duct were reconstructed with a simple inside bracket. Results: Among 65 cases of combined liver-kidney transplantation, the success rate in the late 40 cases was 77.5%. The function of the grafted liver and kidney remained normal. Conclusion: This rat model of combined liver-kidney transplantation can be established in common laboratory conditions with high success rate and meet the needs of renal transplantation experiment.  相似文献   

13.
目的:评价使用安心颗粒对急诊经皮冠状动脉介入术(PPCI)术后生活质量的影响.方法:将160例接受PPCI的急性ST段抬高型心肌梗死患者随机分为安心颗粒组(术前顿服安心颗粒8.8g,术后安心颗粒4.4 g/次,每日2次)和对照组(仅接受基础药物治疗).所有患者均服用阿司匹林、氯吡格雷和阿托伐他汀.分别在入院时、出院前1d、出院后180 d时,应用心肌梗死多维度量表(MIDAS)、中文版SF-36评价量表对患者生活质量评分.并观察术后30 d以内的出血并发症、血小板减少症发生情况.结果:入院时和出院前1d,两组患者的心肌梗死MIDAS、SF-36量表评分比较无差异(P>0.05);出院后180 d时,与对照组比较,安心颗粒组MIDAS、SF-36评分明显减低(P<0.05);组内与入院时比较,两组出院前1d、出院后180 d时,MIDAS、SF-36评分均降低(P<0.05).两组患者在随访期间均无大量出血、少量出血、重度和极重度血小板减少症发生,安心颗粒组有4例、对照组有7例发生不明显出血(P>0.05).两组发生轻度血小板减少症的患者数比较无差异(P>0.05).结论:PPCI使用安心颗粒,能改善急性ST段抬高型心肌梗死患者的生活质量,且不增加出血风险.  相似文献   

14.
Objective:To investigate the influences of urapidil and nicardipine on rabbit sinus function,atrio-ventricular node function and hemodynamics.Methods:Thirty-two Angora's rabbits were selected and randomly divided into four groups.U1 group:urapidil 0.25 mg/kg;U2 group:urapidil 0.5 mg/kg;N1 group:nicardipine 10 μg/kg;N2 group:nicardipine 20 μg/kg.All these medicine were administrated within 30 seconds.Measurements were taken before and after the administration of urapidil or nicardipine for the following data:mean blood pressure(MAP),heart rate(HR),sino-atrial conduction time(SACT),maximal sinoatrial recovery time(SNRTmax)corrected sinus node recovery time(CSNRT),index of sinus node recovery time(SNRTI),Wenckebach A-V conduction frequency (WB),and P-R interval.Results:Significant MAP and HR changes were identified in all of the four groups before and after administration of both urapidil and nicardipine.No significant changes could be found in the rest of the parameters.Intergroup analysis showed that SACT and CSNRT of N1 and N2 groups were shorter than those of the U2 group(P<0.01);the MAP decreased(P<0.01)and the HR increased drastically(P<0.01).Conclusions:Neither urapidil(0.25 mg/kg,0.5 mg/kg)nor nicardipine(10μg/kg,20μg/kg)has any significant influence on rabbit sinus function or rabbit atrio-ventricular node function.Nicardipine could be a better choice than urapidil for parafunctional sinus node patients.  相似文献   

15.
Objective:To investigate the gene expression of osteoprotegerin(OPG) and osteoclast differentiation factor(ODF) in the bone tissue of patients with hip fracture due to osteoporosis. Methods:OPGmRNA and ODFmRNA in the bone tissue in 50 cases of osteoporosis sufferers(over 50 years old) with hip fracture(Observer Group) and 30 cases of hip facture sufferers with no osteoporosis(Control group) were analyzed with the Semi-Quantitative RT-PCR method. Results:The mRNA expressed of ODF, OPG were both high in the patients with hip fracture. In the control group, the expression of OPG mRNA was observed, while the expression of ODF mRNA was very slight. Conclusion:Aged patients contained all signals including OPG, ODF that are essential for inducing osteoclastogenesis and promoting bone resorption.  相似文献   

16.
Objective:To investigate the clinical features, pathological characteristics and immunophenotype of solid-pseudopapillary tumor of the pancreas(SPTP). Methods:Nine surgically treated cases of SPTP were retrospectively reviewed. Hematoxylin and Eosin(HE) staining and immunohistochemical staining were used to analyze all cases, and the general clinical data was collected. Results:Six patients were asymptomatic except for a palpable mass. Two patients complained of vague-epigastric pain. One patient appeared jaundice. The tumor was encapsulated and solid tissues alternately with cystic tissues. Histologically, the histological structure of solid portion was pseudopapillary with a fibrovascular core. Tumor cells were uniform and medium-sized which were arranged in sheets ets or nests or pseudopapillary patterns. Immunohistochemical studies demonstrated that SPTP proved positive in vimentin(9/9 cases), AAT(9/9 cases), NSE(9/9 cases), ACT(7/9 cases), CK20(2/9 cases), CgA(1/9 cases), S-100(3/gcases), PR(4/gcases), Syn(3/9 cases) and CD56(5/9cases), negative in CEA and ER. Conclusion:SPTP is a tumor predominantly occurring in young women frequently without special symptoms. This tumor has various characteristical histological patterns with different immunophenotype.  相似文献   

17.
In recent years, the author of this essay has applied electro-acupuncture combined with the trigger point needle-embedding for treatment of primary trigeminal neuralgia in 31 cases, yielding satis- factory results as reported in the following.  相似文献   

18.
Objective: To explore the role of matrix metalloproteinase-1,2 (MMP-1, MMP-2) and tissue inhibitor of matrix metalloproteinases-1 (TIMP-1) in endometriosis. Methods: The eutopic and ectopic endometria from 40 subjects suffering from endometriosis and regular.endometria from 40 subjects (excluding endometriosis) were collected and examined by in situ hybridization technology and western blot assay. Results: Both expressions of MMP-1 and -2 were stronger in ectopic endometrium and eutopic endometrium than in normal endometrium. On the contrary, the expression of TIMP-1 in ectopic endometrium and eutopic endometrium was lower. The differences were significant (P 〈 0.01 ). Moreover, there was no relationship among the expressions of MMP-1, 2 and TIMP-1 in ectopic endometrium. Conclusion: The expressions of MMP-1, 2 and TIMP-1 lose balance and lack of periodic changes in ectopic endometrium , which explains the biological invasive behavior of endometriosis. It was suggested-that regulating the balance between the MMPs and TIMP-1 should be an ideal therapeutic target to endometriosis.  相似文献   

19.
Prof. SHI Da-zhuo, Ph.D., male, was born on March 20, 1960. Prof. SHI entered the Ph.D. program in 1990 at the China Academy of Chinese Medical Sciences under the supervision of Prof. CHEN Ke-ji, majoring in the treatment of cardiovascular diseases. After receiving his Ph.D. degree in 1993, Prof. SHI started working at the Cardiovascular Center in Xiyuan Hospital affiliated to China Academy of Chinese Medical sciences.  相似文献   

20.
《中国结合医学杂志》2008,14(2):159-159
The 6th National General Congress of Chinese Association of Integrative Medicine (CALM) was convened at 19-20, April 2008 in Beijing. Academician CHEN Zhu, the minister of Ministry of Health indicated at the congress that the integration of Chinese and Western medicine is very well in keeping with the situation of our country and the general rule of development in medical science; and as a good integration of Chinese medicine and Western medicine, it is mutually beneficial and advantageous to both of them. Seeing the creativity shown in integrative medical investigation in theoretic and methodological sides, we should and must persist in and develop it.  相似文献   

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