基于粒子群优化的无线传感器网络节点定位改进

针对无线传感器网络低成本、低功耗的要求, 提出了一种DV-Hop改进算法, 利用节点间的估计距离和锚节点的位置, 在DV-Hop算法的第三阶段使用粒子群优化的方法校正DV-Hop得到的估算位置。该算法不需要任何额外硬件设备和不增加通信量。仿真表明, 改进的算法可以使DV-Hop的平均定位误差下降30%, 并有效降低了成本

Determination of nine triazole pesticides in environmental waters using solid phase extraction and gas chromatography-mass spectrometry

应用C18柱萃取/富集,NH2柱净化,气相色谱-质谱联用技术检测,建立了环境水样中9种三唑类农药同时分析的方法。9种目标农药在0.025～0.500mg/L质量浓度范围内线性关系良好,方法的检出限为0.002～0.009μg/L。以实际水样为基底,加标质量浓度为0.025μg/L和0.100μg/L时,9种目标农药的基底加标回收率和相对标准偏差(n=3)分别为68.4%～113.9%,1.6%～6.9%(河水)和70.3%～115.2%,0.8%～8.2%(海水)。该方法操作简单、灵敏度高、选择性好,符合多种农药残留分析的要求,并成功地应用于福建九龙江河口区表层水样中三唑类农药的残留状况调查。A method was developed for the simultaneous determination of 9 triazole pesticides in environmental water using C18 cartridge for the extraction and enrichment,NH2 cartridge for the clean-up and gas chromatography-mass spectrometry for the detection.The linear range of calibration curves for the 9 target pesticides was between 0.025 mg/L and 0.500 mg/L.The detection limits were in the range of 0.002-0.009 μg/L.The 9 target pesticides were measured in river water and sea water at 0.025 μg/L and 0.100 μg/L spiking levels,recoveries and relative standard deviations(RSD,n=3)were 68.4%-113.9% and 1.6%-6.9% for river water and 70.3%-115.2% and 0.8%-8.2% for sea water,respectively.The method is simple,sensitive,selective and suitable for the qualification of pesticide multiresidue analysis.It has been successfully applied to the survey of 9 triazole pesticide residues in Jiulong River Estuary,Fujian.福建省自然科学基金项目(No.2006J0140

Auto-controlled System of Hydraulic Log-core Veneer Lathe

设计的液压无卡轴旋切机自动控制系统采用C8051f020为控制器控制旋切机液压系统的进给,用位移传感器检测并反馈圆木直径,建立了旋切过程中刀刃进给速度与圆木直径的数学模型,同时推导出了液压系统流量的计算公式。以单片机C8051f020为核心,设计了系统的模/数转换和数/模转换的关键外部硬件电路和控制系统软件。采用这种流量控制技术,提高了旋切机进给的精度和工作效率。An automatic control system of hydraulic log-core veneer lathe based on C8051F020 is studied in this paper.C8051F020 is used to control the hydraulic system feeding.The displacement sensor is used to measure the diameter of the round log.The mathematical model between the knife-carriage feeding speed and the diameter of the log is established;the flow mathematical model of the hydraulic system is also derived.Taking single chip computer C8051F020 as core the A/D and D/A switching of key external hard ware circuits and control system software are designed.The electro-hydraulic control technology has been used in the Log-core veneer Lathe;the precision of the working veneer,the working efficiency and the lifetime of the Log-core veneer Lathe can be highly improved

监护病房与普通病房倒班护士工作负载的比较

应用高效液相色谱法测定尿内儿茶酚胺排出量,对36名监护病房和普通病房倒班护士工作负载作了比较。结果表明:监护病房护士日班和大夜班的工作负载较普通病房护士重些,且监护病房护士以心理负荷为主,普通病房护士以体力负荷为主;而两组被试小夜班工作负载的情形相类似。此外,还以被试对工作负载、心境变化和睡眠情况的自我评定作为参考。</p

Expression of the coat protein gene of IHHNV in shrimp in Pichia Pastoris

对虾传染性皮下及造血组织坏死病毒是“须向OIE申报的甲壳动物重要疾病“之一。将该病毒主要结构蛋白基因克隆至毕赤酵母穿梭表达质粒PPIC9k,构建重组表达载体(命名为PPIC9k-IV),限制性内切酶bglⅡ对其进行酶切线性化,采用电穿孔法转化到毕赤酵母gS115宿主菌。采用PCr方法分析和g418筛选来鉴定重组的毕赤酵母,诱导表达的产物分别进行ElISA分析或WESTErn blOT免疫印迹鉴定,分泌表达产物分子量大小为40ku左右,原核表达时制备的兔抗对虾传染性皮下及造血组织坏死病毒衣壳蛋白的血清可与真核表达的目的蛋白发生特异性反应。The infectious hypodermal & haematopoietic necrosis virus is one of the main diseases of the penaeid shrimp.The gene of coat protein of IHHNV was constructed into Pichia Pastoris secretory expression vectors pPIC9K,named pPIC9K-IV.The recombinant plasmid pPIC9K-IV was linearized with BglⅡ,and then was transformed into Pichia Pastoris GS115 by electroporation.After PCR analysis and G418 screening,the pPIC9KIV recombinant was expressed with 0.8%(V/V) methanol.The expression product was confirmed by Western blot and ELISA analysis.The results showed that the coat protein was successfully expressed,its product was about 40ku,and could recognized specifically by rabbit polyclonal anti-serum.国家质检总局科技基金资助项目(2006IK015

A study of size fraction of colloidal iron in coastal waters utilizing centrifugal ultrafiltration

建立了基于离心超滤技术的近岸海水中络合态铁(fE)粒径分级方法。经0.45μM滤膜过滤的海水样品,分别用不同孔径(3 k dA、10 k dA、30 k dA、100 k dA)的超滤膜离心超滤并脱盐。不同分子量范围的化合物富集于相应孔径的超滤膜上,以酸溶液提取出fE,用原子吸收光谱法(gfAAS)测定。在优化的条件下,方法检测限为0.10μg·l-1,线性范围0.25~10μg·l-1,4组不同孔径超滤膜测定同一份样品的相对标准偏差(rSd)为6.4%~10.3%。本方法成功应用于福建九龙江口至厦门西海域水样的测定,结果显示各分子量范围内的络合态fE含量随盐度增高而降低,且呈非保守分布的变化趋势。Centrifugal ultrafiltration technique has been used for size fraction of colloidal iron in coastal waters in present studies.The seawater sample, which had been filtered through the 0.45 μm membrane, was filtered and desalted by centrifugal ultrafiltration with different pore sizes of membranes( 3 k Da, 10 k Da, 30 k Da, 100 k Da).The colloids in different molecular weight ranges were filtrated on the corresponding membranes.Colloidal iron was extracted with acid solution and detected with graphite furnace atomic absorption spectrometry(GFAAS).Under the optimized conditions, the detection limit was 0.10 μg·L-1, and the linear range was 0~10 μg·L-1.Using different pore sizes of membranes, the relative standard deviations(RSDs) for the same coastal water sample were in the range of 6.4 %~10.3 %( n=4).The proposed method had been successfully applied to analyze the samples collected from Jiulongjiang Estuary and Western Xiamen Harbour, Fujian, China.The concentrations of colloidal iron in every range of molecular weight decreased as salinity increased and the trends indicated a non-conservative mixing process in the studied area.国家自然科学基金(41176075

Absolute Asymmetric Synthesis and Resolution Mechanism of Chiralcis-bromoamminebis(ethylenediamine)cobalt(III) Bromide

分别用绝对不对称合成和改进的拆分方法制备标题配合物!-(+)D-cis-[CoBr(NH3)(en)2]Br2(1)和"-(-)D-cis-[CoBr(NH3)(en)2]Br2(2),以及制备了cis-[CoBr(NH3)(en)2]Br·22H2O(3)(en=1,2-乙二胺).用元素分析、差热-热重、旋光度、UV-Vis、CD光谱等对产物进行了表征.通过CD光谱法获得了绝对不对称合成Co(III)配合物的产物ee值分布图.当利用绝对不对称合成得到的手性Co(III)配合物去“逆向拆分”外消旋溴代樟脑磺酸铵[NH4(dl-BCS)]时只获得部分拆分,初步认为这与交互拆分过程中阴阳离子之间的有效手性识别有关,对于手性Co(III)配合物的绝对不对称合成还提出了一个新的反应机理,即“催化-结晶诱导”机理.The absolute asymmetric synthesis of the title complexes ?撰-(+)D-cis-[CoBr(NH3)(en)2]Br2(1) and ?驻-(-)D-cis-[CoBr(NH3)(en)2]Br2(2)(en=1,2-ethylenediamine) as well as the improved optical resolution of cis-[CoBr(NH3)(en)2]Br2·2H2O(3) are described in detail. The products were characterized by means of elemental analysis, TG-DTA, optical rotation, UV-Vis, and CD spectra. The distribution of enantiomeric excess(ee) of cis-[CoBr(NH3)(en)2]Br2 in the absolute asymmetric synthesis was obtained by the measurements of their CD spectra. It was found that the complete resolution of rac-cis-[CoBr(NH3)(en)2]Br2·2H2O was achieved by use of NH4(d-BCS) (ammonium d-α-bromocamphor-π-sulfonate) or NH4(l-BCS) while NH4(dl-BCS) could only be partially resolved by chiral cis-[CoBr(NH3)(en)2]Br2 at the same condition. It is deduced that there are notable differences in the chiral discrimination of the reciprocal resolution between cis-[CoBr(NH3)(en)2]Br2 and NH4BCS. Moreover, a new "catalysis-crystal induction" mechanism in the preparation of the chiral Co(III) complex is put forward.国家自然科学基金(20171037,20373056);; 福建省自然科学基金(C0020001)资助项

壳寡糖和聚丙烯酸的自组装行为

研究了壳寡糖和聚丙烯酸在共同溶剂水中的自组装行为.两种聚电解质之间不仅存在库仑力,而且存在相当强的氢键相互作用.在超声波作用下,能形成亚微米尺寸的球形自组装聚集体,并利用动态光散射的方法和透射电镜研究了这种自组装微球的尺寸和形态

“加速城市化”不应成为中国“十二五”规划的重大战略抉择——与陈玉和教授等商榷

近年来我国城市化速度和世界同期相比已经很快,也并不滞后于经济发展。加速城市化不应成为我国城市化的长期目标,通过加速城市化促进经济发展往往达不到预期目标,城市化发展需要多维支撑系统。"十二五"时期以及更长时期,我国城市化应适时提出健康城市化(或新型城市化),走可持续发展的城市化道路