79 research outputs found

    陕西省87株耐药结核分枝杆菌寡核苷酸基因分型和耐药性分析

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    目的对陕西87例耐药结核分枝杆菌进行分型研究,了解不同基因型在陕西的流行情况及耐药相关性。方法收集陕西省结核分枝杆菌耐药菌株87株,采用Spoligotyping方法对结核分枝杆菌临床分离株进行基因分型。结果 87株耐药结核分枝杆菌中北京家族占86.21%(75/87),非北京家族占13.79%(12/87);非北京基因型中,T家族(T1、T2、T2-3、T3)占9.20%(8/87),Manu家族占1.15%(1/87),新发现基因型占3.45%(3/87)。北京家族和非北京家族的单耐药、多耐药、耐多药、其他类型耐药比率分别为38.67%(29/75)、13.33%(10/75)、42.67%(32/75)、5.33%(4/75)和66.67%(6/9)、11.11%(1/9)、22.22%(2/9)、0.00(0/3),差异均无统计学意义(P>0.05)。结论陕西省结核分枝杆菌呈基因多态性,其主要流行基因型为北京家族;北京家族和非北京家族的耐药性差异无统计学意义。陕西省社会发展科技攻关项目(No.2016SF-272

    喀斯特原生天坑垂直梯度上植物多样性特征——以云南沾益天坑为例

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    规模宏大的地表负地形——喀斯特天坑具有巨大的容积和陡峭圈闭的岩壁,在坑底形成异于坑外的独特微生境,是研究物种组成和多样性的理想场所,但目前鲜少对喀斯特天坑植物群落的生态过程及其空间变化特征进行探讨。本研究以云南沾益大毛寺原生天坑植物群落为研究对象,通过游动分割窗技术以及边缘效应值、边缘效应强度和β多样性指数的计算,对原生天坑\"坑边缘—坑壁—坑底\"的生态交错带进行定量判定,探讨垂直环境梯度上植物群落物种多样性变化特征及天坑内外物种多样性边缘效应特征。研究结果表明,原生天坑\"坑边缘—坑壁—坑底\"垂直梯度上的生态交错带出现在坑壁中域位置,宽度大约为40 m,是连接天坑内外生态系统的一个特殊生态过渡带;天坑内外植物群落在坑壁出现\"断裂\",存在不同于一般生态交错带的\"边缘负效应\";基于β多样性指数,垂直环境梯度上植物物种更替率总体呈上升趋势,坑底与坑边缘的植物群落物种组成存在较大差异,坑底拥有更高的物种丰富度和多样性,具有重要的物种多样性保护库价值

    Oil Spill identification by near-infrared spectroscopy coupled with clustering analysis based on principle components

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    鉴于目前没有一种方法能独立解决溢油鉴别的所有问题,本文提出了近红外光谱技术结合主成分聚类分析鉴别溢油种类的方法。通过有机溶剂萃取出自行配制的汽油、柴油和润滑油模拟样品中的溢油后记录其近红外光谱,对5800~6200cm-1区段范围内的谱图经多元散射校正(MSC)、Norris一阶导数平滑预处理处理后求其主成分,并在主成分的基础上引入Ward聚类分析法(离差平方和法)对样品分类。结果表明近红外光谱技术结合聚类分析能对体积分数在0.4~0.8mL/L间的海面溢油样品正确、快速分类,近红外光谱技术结合主成分聚类可作为溢油鉴别的一种辅助方法。Owing to none of the existing method can do it all for oil identification, but a method by near-infrared spectroscopy (NIR) coupled with clustering based on principle components is proposed. Petroleum oil stimulating samples of gasoline, diesel fuel and lubricating oil were employed to develop the method. NIR spectra ranges of 5800~6200cm~(-1) were recorded with the multiplicative signal correction and Norris first derivative filter pretreatments. The clustering analysis by Ward's method base on the different principle components was discussed. The results show that the method provides the rapid and accurate classification for spilled oil with concentration between 0.4~0.8 μL/L.国家高技术发展计划(863)资助项目(2001AA635040

    喀斯特原生天坑植物群落空间格局特征——以云南沾益天坑为例

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    以云南沾益大毛寺原生天坑为例,获取坑内植物群落林木个体相对位置信息,进行角尺度、混交度、林层指数等林木空间结构参数与坑底植物群落空间格局分析,并运用点格局分析方法进行单个种群的空间分布特征以及不同种群间的空间关联性分析.结果表明:大毛寺原生天坑坑底植物群落在空间分布上呈现随机分布,林木物种呈中度混交,林木垂直分层虽较简单,但结构稳定,具有发育成熟的顶极森林群落的空间分布特征;坑底植物群落的种群主要呈聚集分布,种群间呈负关联,且处于同一垂直层次上种群间空间负相关性更强,垂直层次相差越大,空间竞争性越小,而随着空间范围的增大,空间负关联越弱;坑内生态系统具有较高的稳定性,是难得的物种自然栖息地和生态避难所,独特生境中形成的稳定植物群落结构在喀斯特地区生态恢复研究中具有重要的借鉴意义和导向作用.国家重点研发计划项目(2016YFC0502900)资助~

    Enantioseparation of 1,1'-bi-2-naphthol benzoates using high performance liquid chromatography

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    采用CHIrEX(S)-lEu&(S)-nEA、CHIrAlCElOd-H和CHIrAlPAkAd-H手性色谱柱直接拆分了2′-羟基-1,1′-联萘-2-苯甲酸酯(Hbnb)、1,1′-联萘-2,2′-二苯甲酸酯(bndb)和2′-甲氧基-1,1′-联萘-2-苯甲酸酯(Mbnb)对映体。分别考察了流动相组成、柱温和化合物结构对手性分离的影响。结果表明:3对联萘二酚苯甲酸酯对映体在CHIrAlPAkAd-H柱上的拆分效果最好。当采用正己烷/异丙醇(40/60,V/V)为流动相时,Hbnb、bndb和Mbnb对映体的分离因子(α)和分离度(rS)分别为1.76、1.74、1.40和6.47、7.81、4.75。对比联萘二酚(bn)的分离,从联萘分子中2-位取代基、对映体出峰顺序和热力学参数等方面探讨了相关手性分离机理。The enantioseparations of 2'-hydroxy-1,1'-binaphthyl-2-yl benzoate(HBNB),1,1'-binaphthyl-2,2'-diyl dibenzoate(BNDB) and 2'-methoxy-1,1'-binaphthyl-2-yl benzoate(MBNB) were studied on Chirex(S)-LEU &(S)-NEA,cellulose tris(3,5-dimethylphenylcarbamate)(Chiralcel OD-H) and amylose tris(3,5-dimethylphenyl-carbamate)(Chiralpak AD-H) columns,respectively,using high performance liquid chromatography.The effects of mobile phase,column temperature and compound structures on the enantioseparations were discussed.The Chiralpak AD-H exhibited stronger capability of enantioseparation in comparison with those of Chirex(S)-LEU &(S)-NEA and Chiralcel OD-H for 1,1'-bi-2-naphthol benzoates.When using the mobile phase of n-hexane/2-propanol(40/60,v/v),the chiral selectivities of HBNB,BNDB and MBNB were 1.76,1.74,and 1.40,respectively.Moreover,in comparison with that of 1,1'-bi-2-naphthol(BN),the mechanisms of the enantioseparation of 1,1'-bi-2-naphthol benzoates,related to the substituted groups at 2-position,the elution orders and thermodynamic parameters were also discussed.国家基础科学人才培养基金项目(No.J0630429

    The Circuit Design of Piezoelectric Jetting Dispensing Control System

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    基于新型压电式点胶头采用的双压电陶瓷的推挽驱动作为胶体喷射的作用机制,设计并搭建了压电式喷射点胶控制系统,完成了硬件与软件模块的组装调试,实现对下压电陶瓷信号的频率、占空比、幅值、上压电陶瓷信号幅值的连续可调,具备人机交互、清洗、喷射点数可调等功能。经测试,系统各参数达到预定指标,频率显示误差:±1.2 Hz;占空比显示误差:±1%;幅值显示误差:±8 MV。在驱动方波电压200 V、频率65 Hz、占空比20%、喷嘴直径250μM、供料压力4 bAr、喷射高度3.5 MM的条件下,得到平均直径为1.07 MM左右的喷射胶滴,一致性误差为±2%。According to the working principle of newly piezoelectric dispensing head,which using the pushed driving of double piezoelectric ceramic for colloform jetting,we design and establish this piezoelectric jetting dispensing control system.Meanwhile,package the hardware and debug the software,achieve the goal that frequency,duty cycle and amplitude of the lower piezoelectric ceramic signal,amplitude of the upper piezoelectric ceramic signal can be continuously adjusted.The system has the function of man-machine interaction,cleaning,regulating injection points,and so on.After tested,all of the system parameters can meet the presupposed index,with the frequency display error: ±1.2 Hz,duty cycle display error: ±1%,amplitude display error: ±8 mV.Under the condition that voltage of the driving squarewave 200 V,frequency 65 Hz,duty cycle 20%,diameter of nozzle 250 μm,pressure 4 bar,height of jetting 3.5 mm,we get the jetting drops with an average diameter of 1.07 mm,and its conformity error ±2%.中央高校基金科研业务费专项资金资助项目(2010121039

    Research on siderophore secreted by Prorocentrum donghaiense Lu under iron-limited conditions

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    在铁限制条件下,进行东海原甲藻分泌铁载体的动态研究。对藻类在富铁与缺铁条件下生长状况、生长过程中分泌铁载体的情况以及海藻接种量对铁载体分泌的影响进行了连续观测,结果表明:东海原甲藻在缺铁条件下生长状况远不如在富铁条件下;随着藻类的生长,分泌铁载体不断增多,达指数生长期时,其分泌量也达到了最大值,之后藻类的生长和铁载体分泌都呈现下降趋势;高接种量东海原甲藻能分泌较多的铁载体,并在较短时间到达峰值。Under iron-limited conditions,marine microorganisms are able to secrete low-molecular-weight,highly specific iron chelators termed siderophores.These compounds scavenge iron from protein complexes or insoluble hydroxides in the extracellular environment and transport it to the cell cytosol via a membrane-bound receptor protein in the microorganism.Iron is a necessary requirement in marine ecosystems.Therefore research on siderophores is very significant to interpretation of high nitrate low chlorophyll(HNLC) regions and iron hypothesis.However,it is not clear whether eukaryotic phytoplankton can produce the iron-specific chelating compounds.Therefore,a systematic investigation was carried out for siderophore secreted by P.donghaiense Lu under iron-limited conditions.Parameters studied included the growth of the algae in iron-added and iron-deficient medium,the secretion of siderophore during algae growth,and the effect of algae population inoculated on the siderophore production.Results showed that the algae growth rate in iron-deficient medium was slower than those in iron-rich medium.Under iron-limited conditions,the siderophore production increased along with algae growth.Maximum production was observed in the exponential growth period.Thereafter the rate of algae growth and siderophore secretion started to decrease.Furthermore,increasing algae populationt resulted in secreting more siderophore and shortening the time needed to reach maximum production.国家高技术研究发展计划资助项目(2001AA635040);; 国家海洋局青年基金资助项目(2005102);; 国家重点基础研究发展规划资助项目(2001CB409702);; 青岛市科技将材计划资助项目~

    Analysis on epidemiological charateristics of chlamydia trachomatis infection in Jiangsu Province,2006-2011

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    目的了解江苏省2006-2011年生殖道沙眼衣原体感染的流行病学特征,为制定防治生殖道沙眼衣原体感染的策略提供科学依据。方法收集2006-2011年江苏省通过中国疾病预防控制信息系统报告的生殖道沙眼衣原体感染病例资料,并对资料进行流行病学分析。结果 2006-2011年,江苏省生殖道沙眼衣原体感染发病率呈快速上升的趋势,2006年为0.12/10万,2011年为3.15/10万,发病率年均增长速度为92.23%;在报告的5 859例病例中,男女性别比为0.3∶1,各年生殖道沙眼衣原体感染男女性别差异有统计学意义;发病年龄主要集中在20~29岁年龄组,占50.96%;江苏省生殖道沙眼衣原体感染报告病例主要集中在苏南和苏中的较发达城市;主要以家庭及待业者和工人为主。结论江苏省生殖道沙眼衣原体感染发病率快速增长,应加强对生殖道沙眼衣原体的防治,以控制其感染的快速流行。江苏省医学重点人才(RC2011086);江苏省医学重点人才(RC2011087); 江苏省科技项目(Y201029

    关于“经济发展方式转变进程中的财税政策”的探讨(笔谈)

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    转变经济发展方式是当前中国的热门话题,而上海在城市发展中又肩负着率先转变的重要任务,在这一意义和背景下,2010年4月24日由上海金融学院学院主办、上海金融学院公共经济管理学院承办的“《中国城市财政发展报告2009/2010:促进‘两个中心’建设的上海城市财政》首发式暨‘经济发展方式转变进程中的财税政策’论坛“在我校举行。与会专家围绕经济发展方式转变进程中的财税政策的“趋势与目标“、“机遇和挑战“、“实施方略“和“地方实践“等四个专题进行研讨,各抒己见,智慧交锋。现将其真知灼见整理摘要与读者分享,以期待更多学者共同关注当前经济发展方式转变进程中的财税政策

    Research on Resonance Characteristic of Silicon Micro Resonator under Abnormal Environment

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    随着微器件的商业化,非常态工作环境成了影响器件高精度与可靠性获得的重要因素。作为这些微结构的核心元件,微谐振器在非常态环境下的谐振特性研究变得越来越重要。本论文以微谐振器为研究对象,设计温度敏感与阻尼敏感两类谐振器结构,从理论推导、建模仿真与实验验证三方面研究微谐振器谐振频率的温度变化规律,以及系统阻尼与真空关系。主要研究内容和成果如下: 1)简述典型支撑梁固有频率的温度系数模型,梳理支撑梁温度敏感参数,分析温度影响支撑梁固有频率的规律性机制,并以此作为设计目标,对典型支撑梁进行结构参数化仿真。仿真结果表明:在温度环境作用下,直脚梁、蟹脚梁与折叠梁支撑结构的谐振频率都随温度增高而线性减小;梁...With the commercialization of micro devices, abnormal working condition becomes key factor that affects the acquisition of high precision and reliability of micro devices. Since the microresonator is the core component of these microstructures, research on its resonant characteristics in abnormal working condition becomes increasingly important. Therefore with micro resonator as the research objec...学位:工程硕士院系专业:物理与机电工程学院_机械工程学号:1992011115278
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