固相萃取-高效液相色谱法测定玉米中伏马毒素B_1

研究了固相萃取 高效液相色谱法测定玉米中伏马毒素B1的方法。玉米样品经乙腈 0.1mol/ml磷酸二氢钠(1+1)提取,提取液通过固相萃取柱净化,净化液经柱前衍生,ShimadzuSTRODS色谱柱分离,荧光检测器检测,外标法定量。对添加不同含量水平的伏马毒素B1,5次重复实验的平均回收率为82.1%～87.8%,变异系数(CV)为4.7%～7.8%,检测低限为0.020mg/kg。     

固相萃取-高效液相色谱法测定玉米中伏马毒素B1

研究了固相萃取-高效液相色谱法测定玉米中伏马毒素B1的方法.玉米样品经乙腈-0.1 mol/ml磷酸二氢钠(1+1)提取,提取液通过固相萃取柱净化,净化液经柱前衍生,Shimadzu STRODS色谱柱分离,荧光检测器检测,外标法定量.对添加不同含量水平的伏马毒素B1,5次重复实验的平均回收率为82.1%～87.8%,变异系数(CV)为4.7%～7.8%,检测低限为0.020 mg/kg.     

底泥中多种有机氯及拟除虫菊酯类农药残留同时测定法

气相色谱法同时测定章江、贡江底泥中多种有机氯及拟除虫菊酯类农药．以石油醚-丙酮（4：1）超声波提取,有机氯农药回收率82．4％-115．2％,相对标准偏差为2．22％-7．69％（n=5）;拟除虫菊酯类农药回收率84.3％-110．5％,相对标准偏差为2．49％-8．69％（n=5）;方法适用于底泥样品中农药残留测定．     

野菊叶中绿原酸及木犀草素-7-O-葡萄糖苷测定

建立应用高效液相色谱测定野菊叶中绿原酸及木犀草素-7-O-葡萄糖苷含量的方法.以0.04%磷酸-乙腈为流动相,流速为1.0 mL/min,梯度洗脱,检测波长355 nm,结果表明绿原酸浓度10-100μg/mL范围内线性关系良好,相关系数r=0.997;平均回收率为96.7%,相对标准偏差（RSD）为0.85%（n=6）.木犀草素-7-O-葡萄糖苷浓度1-10μg/mL范围内线性关系良好,r=0.999;平均回收率为92.6%,RSD为0.63%（n=6）.     

棉纺织品中7种残留拟除虫菊酯杀虫剂的检测

建立同时提取和分析棉纺织品中7种拟除虫菊酯类农药残留样品的方法.使用气相色谱-质谱联用仪、弱极性HP-5 MS毛细管色谱柱,选择进样口温度250℃、0.6 mL/min的载气流速(氦气),在梯度升温条件下分离分析出7种拟除虫菊酯杀虫剂及异构体,产生17个色谱峰,分离效果较好.使用V正己烷/V丙酮=4∶1的混合溶剂采用超声提取法提取纺织品中残留农药,7种农药的工作曲线呈较好的线性关系(r0.99),且检测限低,在3个加标水平下进行了回收率和精密度实验,回收率在68.6%~99.8%之间,平行测定相对标准偏差为1.43%~13.20%(n=6).本方法回收率高,重现性好,满足Oeko-Tex Standard 100的要求,可作为生态纺织品中拟除虫菊酯杀虫剂的分离分析方法.     

Preparation and Performance of Hollow Spherical Li_4Ti_5O_(12) Doped by Mg~(2+)

The microstructure and performance of Li_4Ti_5O_(12) doped by Mg prepared by hydrothermal method and solid phase method were investigated. Lithium dihydrate, magnesium acetate and tetrabutyl titanate were used as the main raw materials. This study reveals that Mg~(2+) has influences on the spherical structure, crystal development of Li_4Ti_5O_(12) and the electrochemical performances. The hollow spherical structure is composed of nano-sheet structure and the nano-sheet structure can be affected by the Mg~(2+) content. For Li4-xMgxTi5 O12, the sheet structure can be refined with the increment of Mg~(2+) content when x value is 0-0.1 and coarsen with the increment of Mg~(2+) content when x value is 0.1-0.2. The hollow spherical Li_4Ti_5O_(12) powders prepared by hydrothermal method have better performance. The optimal Mgdoped amount of hydrothermal method is 0.1. At 0.1 C, the first discharge capacity of Li_(3.9)Mg_(0.1)Ti_5O_(12) prepared through hydrothermal method at 0.1 C and 10 cycles is 182 and 178 m A h g~(-1), respectively.     

Ribbon-like Cu doped V_6O_(13) as Cathode Material for High-performance Lithium Ion Batteries

Ribbon-like Cu doped V_6O_(13) was synthesized via a simple solvothermal approach followed by heat treatment in air.As an cathode material for lithium ion battery,the ribbon-like Cu doped V_6O_(13 )electrode exhibited good capacity retention with a reversible capacity of over 313 m Ah?g~(-1) for up to 50 cycles at 0.1C,as well as a high charge capacity of 306 m Ah?g~(-1) at a high current rate of 1 C,in comparison to undoped V_6O_(13 )electrode(267 m Ah?g~(-1) at 0.1C and 273 m Ah?g~(-1) at 1 C).The high rate capability and better cycleability of the doped electrode can be attributed to the influence of the Cu ions on the mophology and the electronic conductivity of V_6O_(13) during the lithiation and delithiation process.     

高分子生物表面活性剂性质的初步研究

采用醋酸钙不动杆菌QL22～5在以乙醇为唯一碳源的无机盐培养基中发酵生产了一种相对分子量为8．798×10^5的水溶性聚合物。红外光图谱结果表明该聚合物是一种含亲水多糖链和疏水脂链的脂多糖型表面活性剂（HBS-1）。进一步研究HBS-1的增稠性、表（界）面张力和对柴油的乳化性能,结果显示质量分数0.1％的HSB-1水溶液在20℃、45、下的粘度为114．4mPa．S,具有较好的增粘性能。50℃w（HBS-1）=0．05％溶液的表面张力为57mN／m,与煤油的界面张力为13．8mN／m,w（HBS-1）=0．1％可完全乳化柴油。可见HBS-1作为高分子表面活性荆降表（界）面张力的能力并不显著,但它能乳化柴油并稳定乳状液。     

激光干涉条纹锁定系统的设计与实现

为测量λ/4波长以下位移,研制了激光干涉条纹锁定系统。将干涉仪的工作点稳定在暗点,使其具有线性好和灵敏度高等优点。该系统由激光器及稳频装置、干涉系统、检测及控制电路、位移反馈执行机构（压电陶瓷）,以及数据采集系统组成。实验结果表明,所研制的干涉条纹锁定系统在0～0.5 Hz的频带内,其干涉仪的分辨度达到λ/1 500水平;而在0～50 Hz的频带内,其干涉仪的分辨度达到λ/400水平。频谱分析表明,在0.1 Hz和5 Hz时的分辨度分别为7×10-11 m/Hz^1/2和1×10-11 m/Hz^1/2。     

HPLC法检测米曲霉降解体系中氯氰菊酯前处理方法的研究

针对霉菌降解体系中氯氰菊酯HPLC检测结果重复性差的问题,系统研究了HPLC法检测米曲霉降解体系中氯氰菊酯的前处理方法。结果表明,采取培养液全量取样方式可以解决降解体系中氯氰菊酯分散或分布不均的问题;超声辅助乙腈提取法可使菌体内蓄积或菌体表面吸附的氯氰菊酯得到有效释放。HPLC法对经前处理后降解体系中氯氰菊酯含量进行检测,具有精密度高、重复性和稳定性好、加标回收率高的特点。该方法的建立为微生物降解体系中拟除虫菊酯类农药的准确检测提供了方法参考。     

移动床生物膜反应器中的氧传质性能

为提高移动床生物膜反应器中氧传质效率,利用动态溶氧法测定曝气量(0.84～4.2m3/h)、填料填充率(0～30%)、反应器高度(0～0.5m)、溶液中添加表面活性剂十二烷基硫酸钠和电解质NaCl等因素对氧传质系数的影响,结果表明随着曝气量的增大,氧传质系数从0.002 5/s增加到0.066/s,填料固含率在10%时氧传质效果最好;反应器高度主要影响气泡的压力进而影响气液接触面积,随着气泡的上升,氧传质系数从0.011逐渐降低为0.009 6/s;表面活性剂在0～0.015g/L浓度范围内氧传质系数逐渐降低;NaCl通过改变气泡表面的ζ电势和表面张力进而影响氧传质效果,在0～20g/L范围内,氧传质系数随着NaCl浓度的增大而增大.     

野菊菊米和野菊花挥发油化学成分的比较研究

采用水蒸气蒸馏法提取云南产野菊菊米和野菊花挥发油，用气相色谱-质谱联用技术对其化学成分进行分离鉴定，并用面积归一化法测定了相对含量．鉴定出野菊菊米主要化学成分50种，占总化合物的95．00％；野菊花主要化学成分42种，占总化合物的90．95％．野菊菊米和野菊花挥发油的主要成分为单萜烯类、倍半萜烯类及其含氧衍生物等，但其化学成分种类和含量有明显的差别．     

Thermal expansion properties and hygroscopicity of Y2-xSmxW3O12 (x = 0.0-0.4) compounds

A novel class of solid solutions of Y2-xSmxW3O12 (x = 0.0-0.4) were synthesized and studied by means of powder X-ray diffraction. All samples crystallize in an orthorhombic space group Pnca. The lattice parameters a, b and c of Y2-xSmxW3O12 increase with increasing Sm content. Since the compounds of this series hydrate at room temperature, thermogravimetric (TG) analysis was carried out. The result shows that the compound stores less water with increasing Sm content. The thermal expansion properties of Y2-xSmxW3O12 (x = 0.1, 0.3 and 0.4) were investigated with high temperature X-ray diffraction. Negative thermal expansion coefficient -α becomes less negative from -6.644×10-6 to -6.211×10-6℃-1 when x changes from 0.1 to 0.4.     

浸提法提取胶母糖中铅的测定方法

通过采用硝酸过氧化氢过夜浸提改进胶母糖样品中测定铅的前处理方法,基体干扰少,三水平加标回收率在95.2%～110.3%,8次重复测定的变异系数为1.8%,与国家标准方法比较,采用t检验法分析,结果无显著性差异.     

HPLC法同时测定牛黄清胃丸中四种成分的含量

建立同时测定牛黄清胃丸中大黄酸、大黄素、大黄酚和大黄素甲醚含量的HPLC法。方法：采用Diamonsil C18色谱柱（250mm×4.6mm,5μm）,流动相为甲醇-0.1%磷酸（75:25）,柱温为30 ℃,进样量为10μL,流速为1.0 mL·min-1,检测波长为254nm。结果：大黄酸、大黄素、大黄酚和大黄素甲醚的线性范围分别为22.68～113.40μg·mL-1(r=0.9991)、6.25～31.24μg·mL-1(r=0.9996)、14.74～73.68μg·mL-1(r=0.9990)和5.22～26.12μg·mL-1(r=0.9999),平均回收率分别为99.9%（RSD=1.2%,n=6）、99.9%（RSD=1.9 %,n=6）、100.0%（RSD=1.2%,n=6）和99.8%（RSD=1.8%,n=6）。结论：该方法简便、快速、准确,专属性强,样品处理简便,适用于牛黄清胃丸的质量控制。     

光子晶体光纤拉曼激光器研究

利用100m非线性光子晶体光纤，以光纤光栅对作为谐振腔，研制成功了低阈值光子晶体光纤拉曼激光器．该光子晶体光纤拉曼激光器的闽值为2W，在抽运功率6．2W时，得到最大功率为1．8W．波长为1115．9nm的连续拉曼激光输出，拉曼半峰全宽为1．39nm，对应光-光转化效率29％，斜率效率41％．且在低功率连续光泵浦下观察到5级拉曼荧光．     

GC法对中药材中残留农药的多残留分析

建立了中药材中8种有机氯农药和4种拟除虫菊酯农药残留气相色谱分析方法。样品用丙酮-石油醚超声提取,再用正已烷进行液-液分配,提取液用弗罗里硅土柱净化,采用SE-54弹性石英毛细管柱分离,用GC-ECD同时检测。测定结果高、中、低3个水平添加时的回收率为80.6%~119.8%,相对标准偏差为0.7%~9.5%。该方法的检出限为:有机氯农药0.0005~0.007mg/kg,拟除虫菊酯0.005~0.008 mg/kg。通过实验结果显示本方法可用于中药材中农药残留测定。     

关于图是[a,b;m]-均匀图的一个邻域条件

设G是一个n阶的图,并设a和b是整数,使得1≤a＜b,以及δ(G)是G的最小度.证明了:如果δ(G)≥a 1,n≥2(a b)(a b-1)/b,以及ING(x)UNG(y)l≥an/(a b-1) 2对G的任意两个不相邻的顶点x和y都成立,那么G是一个[a,b;m]-均匀图.     

一维太赫兹光滤波器的模拟与制作(英文)

模拟并制作了基于光子带隙结构的一维太赫兹光滤波器.通过人工叠加方式制作一维周期性结构,以聚乙烯或聚四氟乙烯作为高折射率材料,用钻有圆孔的合金片作为空气层,利用太赫兹时域光谱技术测量样品在0.1～0.9 THz波段的透射谱.根据理论模拟结果,利用聚乙烯设计制作中心波长为0.3 THz的带阻滤波器,结构周期为400μm,占空比为0.5.测量的3 dB带宽为0.08 THz,与模拟结果0.07 THz基本吻合.     

Crystal structures and theoretical investigation of anti-/syn-2,4-diphenylpentane- and 2,4-di-p-tolylpentane-2,4-diols

2,4-diphenylpentane- and 2,4-di-p-tolylpentane-2,4-diols were investigated employing experimental and density functional theory (DFT) method at B3LYP/6-31G (d) level. The structure of syn-2,4-di-p-tolylpentane-2,4-diol (2b) was characterized by X-ray diffraction and compared with the crystal structures of anti- and syn-2,4-diphenylpentane-2,4-diols (1a and 1b). X-ray diffraction indicates that inter and intra-molecular hydrogen bonds are formed in the crystal structures. There is π-π staking interaction in 1b and 2b. Good linear correlations and similar results are found between the experimental ¹H and ¹³C NMR chemical shifts (δ _exp) and GIAO (Gauge Independent Atomic Orbital) method calculated magnetic isotropic shielding tensors (δ _calc). HOMO and LUMO molecular orbitals were calculated at the same levels with the different results. UV-vis absorption spectra of the compounds were recorded in EtOH, MeCN, n-BuOH and cyclohexane with different dielectric constants. It is found that the solvent effect is obvious when ɛ is 24.85(EtOH), 35.69(MeCN) and it is weak when ɛ is decreased to 17.33(n-BuOH), 1.18 (cyclohexane).