135 research outputs found

    新生代农民工个人现代性与人际传播——基于上海市调查数据的实证研究

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    以对上海地区新生代农民工的调查数据为依据,考察了新生代农民工个人现代性发展现状,从人际传播的角度分析其对个人现代性形成的影响。研究发现,新生代农民工个人现代性正处于过渡阶段;人际传播网络是其个人现代性的培养环境;人际传播行为是其个人现代性的催化剂。人际传播网规模、传播网趋同性、异质性、人际传播频率和内容等变量对新生代农民工个人现代性有显著影响。国家社科基金项目:新生代农民工信息需求层次与传播机制研究(10CXW030);上海市重点学科“传播学”建设项目(S30102);上海市高校人文社会科学重点研究基地项

    主流媒体第一要提高的是发现力

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    当前\"新媒体\"这个词出现频率过高,暴露出媒体界、新闻传播学界思维时间化的取向,而把优劣问题简单化地用新旧问题取代,不仅是框架失焦,而且是方法失当。最有价值的问题应该是优媒体与劣媒体的问题。传统媒体的自信,新媒体的价值,都要从\"优\"这个源泉里找。媒体融合的目标,不是简单地把新媒体捆绑在传统媒体上,也不是传统媒体搭上新媒体的快车,更不是把传统媒体洗新

    Studies on degradation mechanism of niclosamide ethanolamine salt Ⅰ Determination of niclosamide ethanolamine salt in photolysis solution

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    目的了解氯硝柳胺乙醇胺盐(nES)在水体中的光解规律。方法实验室配置PH5的0.05μg/Ml、PH7的0.5μg/Ml和PH9的2.5μg/MlnES溶液,采用氙灯光源作为模拟日光照射,照射后0、0.5、1、2、4、8、16、24、48、72、96H采集光解液,高效液相色谱法测定光解液中nES含量,同时设无光照对照试验,计算其半衰期。结果在氙灯光光照条件下,nES快速降解,8H3种PH值的nES溶液下降率分别为83.4%、78.8%和41.3%,24H下降率分别为92.1%、88.5%和95.8%。nESPH5半衰期为8.98H,PH7为10.34H,PH9为9.16H;无光照条件下放置12d溶液浓度稳定。结论nES可在水中快速光解。Objective To understand the photolysis mechanism of niclosamide ethanolamine salt(NES) in water body.Methods NES was formulated into solutions of pH 5(0.05 μg/ml),7(0.5 μg/ml) and 9(2.5 μg/ml),respectively.The xenon gas lamp was used as the simulated sunlight.After 0,0.5,1,2,4,8,16,24,48,72,96 h of the illumination,the photolysis solutions were collected to determine the amount of NES by using the high-performance liquid chromatography method(HPLC),and the experiment without illumination was also set as the control.The half-life was calculated.Results Under the illumination of xenon gas lamp,the NES degraded rapidly.The degradation rates were 83.4%,78.8% and 41.3%,respectively for 8 h,and 92.1%,88.5% and 95.8%,respectively for 24 h.The half-life of NES was 8.98 h for pH 5,10.34 h for pH 7,9.16 h for pH 9.The solution could keep stable for 12 d without illumination.Conclusion Photolysis of NES can occur quickly in water.江苏省自然科学基金(BK200602

    大容量试验系统建模方法及一键顺控方案研究

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    大容量试验是检验电力装备性能,保障装备安全可靠运行的重要环节。现有的大容量试验回路主要依靠人工操作,存在流程复杂、效率低且易出错的问题。针对大容量试验回路智能化控制的难题,研究建立了冲击发电机单电机短路模型和双电机并联短路模型,分析了发电机短路特性,结合典型大容量试验回路设计了一键顺控方案,提出试验回路一键顺控操作流程。通过对发电机短路模型和大容量试验回路系统的仿真,验证了所建发电机短路模型的正确性及大容量短路试验一键顺控方案的合理性

    Studies on degradation mechanism of niclosamide ethanolamine salt Ⅱ Isotopic tracing and determination of photolysis end-product

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    目的观察同位素示踪技术解析氯硝柳胺乙醇胺盐(nES)在水体中的稳定性及测定光解终产物CO2的变化。方法实验室配制PH5的0.05μg/Ml、PH7的0.5μg/Ml和PH9的2.5μg/MlnES溶液,采用氙灯光源作为模拟日光照射上述nES溶液,照射8、16、24、32、40、48H和72H后,分别测定nES溶液在光解管顶的气态样品,采用gASbEnCHⅡ进样针插入直接分析;液体样品则取2.5Ml注入用高纯氦吹过的密封顶空样品瓶中,用加酸泵滴加无水磷酸,30℃超声反应1H,再插入gASbEnCHⅡ进样针进行分析;与dElTAPluS/XP稳定同位素质谱仪联用测定光解产物CO2的量及碳稳定同位素。结果在氙灯光光照条件下,PH70.5μg/Ml和PH92.5μg/MlnES溶液的光解,随光照时间的增加,CO2的量也增加,并呈线性增长,72H时其产量接近nES的实际产量。同位素结果显示,随光照时间的增加,CO2的碳同位素值逐渐变负,72H时接近nES原药的碳同位素值,为-25.36±0.11,光降解已接近完全。而PH50.05μg/MlnES溶液的光解,随光照时间的增加,CO2的量也在增加,但其产量超出了nES的实际产量;同位素结果显示,随光照时间的增加,产出CO2的碳同位素值逐渐变负,但在光照16H后其产CO2的碳同位素值比nES的碳同位素值偏负。结论 nES能够在水中快速光解,终产物为CO2。Objective To analyze the stability of niclosamide ethanolamine salt(NES)in water and determine the changes of CO2,the photolysis end-product,by using the isotopic tracing technique.Methods NES was formulated into the solutions of pH 5(0.05 μg/ml),pH 7(0.5 μg/ml)and pH 9(2.5 μg/ml),respectively.The xenon gas lamp was used as the simulated sunlight.After 8,16,24,32,40,48,72 h of the illumination,the gas samples of the NES solution on the top of photolysis tube were determined by using direct insertion of GasBenchII needle.For liquid samples,2.5 ml NES solution was added into a sealed empty bottle,which was treated with high pure helium,and then anhydrous phosphoric acid was added.After ultrasonic reaction at 30 ℃ for 1 h,the GasBenchII needle was inserted for analysis.The amount of CO2 and carbon isotopic value were determined by using the GasBenchII needle combined with isotopic mass spectrometer.Results Under the illumination of xenon gas lamp,the NES solutions of pH 7 and pH 9 occurred photolysis,with the increase of illumination time,the amount of CO2 increased,showing a linear increase.At 72 h,its yield approximated to the active output of NES.The isotopic tracing results showed,with the increase of illumination time,the carbon isotope value of CO2 turned to be negative gradually,and approximately reached to the carbon isotope value(-25.36±0.11‰)of NES active ingredient at 72 h when the photolysis approximated to be completely finished.For the photolysis of pH 5 NES solution,with the increase of illumination time,the amount of CO2 increased,however,its output was more than the active output of NES.The isotopic tracing results showed,with the increase of illumination time,the carbon isotope value of CO2 turned to be negative gradually.However,after illumination for 16 h,the carbon isotope value of CO2 was more negative than that of NES.Conclusions The photolysis of NES can occur rapidly in water,and the end product is CO2.江苏省自然科学基金(BK200602);江苏省卫生厅项目(X200504

    灰绿曲霉产纤维素酶的研究

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    灰绿曲霉(Aspergillus glaucus)发酵液通过硫酸铵盐析、Sephadex G-100分子筛、DEAE Sepharose Fast Flow离子交换柱和Phenyl Sepharose Fast Flow疏水层析,分离纯化一种外切葡聚糖酶(CBH)和一种内切葡聚糖酶(EG).通过SDS-PAGE和凝胶柱层析法测定分子质量表明:CBH全酶分子质量为71 ku,由两个分子质量为35 ku的同型亚基组成;EG为单体蛋白,全酶分子质量为32 ku.酶学性质研究表明:CBH催化pNPC的最适pH为6.0,最适温度为55℃,酶活在pH 5.0~8.0区间和温度低于55℃时稳定;EG催化CMC-Na的最适pH为4.0,最适温度为50℃,酶活在pH3.5~7.5区间和温度低于65℃时稳定.Na+、K+、Ba2+、Mg2+以及NO3-和SO42-对CBH和EG酶活均无影响;Ca2+和Mn2+对CBH有激活作用,Fe2+和Mn2+对EG有激活作用,而Zn2+、Cd2+和Cu2+对CBH和EG均有不同程度的抑制效应.酶动力学分析表明:CBH催化pNPC水解的米氏常数Km值为1.4 mmol/L(pH 6.0,55℃),EG催化CMC-Na水解的米氏常数Km值为5.0 mg/mL(pH 4.0,50℃)

    A quantitative research based on CT three dimensional reconstruct of personalized hip prosthesis and porcine femoral canal fixed

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    目的基于CT三维重建个性化设计猪股骨髋关节假体与骨髓腔接触率的定量研究。方法选择猪股骨,拍摄实验前正侧位,双斜位片,再运用CT进行横断面扫描,获得CT数据后三维重建。基于CT三维重建数据,运用机器人磨削个性化假体,使其成为与髓腔完全匹配的定制假体。匹配后,拍摄实验后正侧位片,计算定制假体与髓腔接触的骨皮质或者骨松质的表面积以及接触率。结果通过计算,个性化假体近端表面与骨髓腔直接接触率为90.8%,与医疗机器人辅助扩髓组获得的假体表面与骨髓腔直接接触率相近,远较传统手工扩髓组获得的假体近端表面与骨髓腔直接接触率高。结论基于CT三维重建个性化股骨假体与猪股骨髓腔初始固定直接接触率为90.8%,可获得良好的接触率。Objective A quantitative research based on CT three dimensional reconstruct of personalized hip prosthesis and porcine femoral canal fixed.Methods Choose a pig femur and get photos of its lateral and double oblique positions before the experiment, then use CT scanning in cross-section.Reconstruct three-dimension on obtaining CT datas, grind personalized prosthesis by using robot and making it perfectly matched with femoral canal of customized prosthesis.Take photos of its lateral when personalized prosthesis matched with femoral canal of pig after the experiment.Then calculate the surface area and contact rate of the cancellous bone or cortical bone respectively where the personalized prosthesis contact with femoral canal.Results Through calculation, personalized prosthesis proximal surface directly contact with the bone marrow cavity at a rate of 90.8% which is close to the rate that prosthesis surface directly contact with the bone marrow cavity which acquired by the medical robot-assisted reaming group.And further the rate is higher than the rate obtained by the traditional manual expanding medullary group.Conclusion The direct contact rate based on CT three dimensional reconstruct of personalized femoral prosthesis and porcine femoral canal initial fixed is 90.8% making it possible to have a good fixed
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