香蕉中噻唑膦残留分析方法研究

建立香蕉中噻唑膦的超高效液相色谱串联质谱法(UPLC-MS/MS)残留测定方法。香蕉样品采用乙腈提取和PSA+C18分散固相萃取,采用UPLC-MS/MS多反应模式(MRM)进行分析测定。噻唑膦在添加水平0.01~1.0 mg/kg范围内,平均回收率为94.3%~107.5%,相对标准偏差为7.9%~11.0%。采用外标法定量,方法的检出限为0.001μg/m L,定量限为0.005 mg/kg。该方法简单、准确、重复性较好且节省溶剂,适用于香蕉中噻唑膦的残留检测。     

实木家具的拆装式结构实现路径探究

遵循结构合理、体积缩小、组装方便、外形美观的设计原则,从拆装式节点实现形式、整体结构拆装方式二个维度系统阐述了实木家具拆装结构实现路径,并对榫自锁可拆式、连接件可拆式两种实木家具拆装式节点形式及椅类、桌台类、柜类、床类家具的整体结构可拆装方式进行了详细介绍,以期为实木家具的结构优化及平板化包装提供思路。     

黄皮的生物学特性研究

通过本试验观察表明:黄皮[Clausena Lansium (Lour.)Skeels]的开花与温度有密切关系,温度高,开花过程短;温度低,开花过程长。花穗中的花轴增长速度也随温度升高而加快,花轴增长快,则花轴长,花穗大;反之,花轴增长速度慢,花轴短,花穗小。黄皮开花的顺序是从花穗基部第1—4个分枝开始,每个分枝则先从基部1—8个二次分枝首先开放。31℃是黄皮花粉萌发最适宜温度。在培养基中加入15—20％蔗糖或2.4—D,三十烷醇等生长调节物质,明显可提高黄皮花粉的萌发力。本试验对黄皮的物候期及植物学特性同时进行了研究。     

一种微生态制剂中抑菌物质的分离与鉴定

植物乳杆菌发酵产生的抑菌物质经乙醇浸提、SephadexG-15层析、氨基酸组成分析、反相液相色谱分离及鉴定，发现该植物乳杆菌产生的抑菌物质为一类分子量较小（小于1000Da)，且比较接近，极性不同的多肽。     

新颖三相异步电动机错相和缺相保护电路

从理论上分析了错相及缺相判别原理，提出了新颖保护电路，其线路简单、实用。     

天目蜜李丰产技术研究

配置一定比例授粉树种，是提高授粉效果获得丰产的基础。授粉树比例幼龄期高于成龄期，授粉树花期应与天目蜜李基本一致、果形近似、品质好、抗性强的优良品种，这样才能确保果品的质量与产量。     

Effect of sodium nitrite and sodium chloride on growth of lactic acid bacteria.

The effect of NaNO2 and NaCl on the growth of 24 lactic acid bacteria strains isolated from vacuum-packed cooked ring sausages were examined by analyzing different growth parameters with Bioscreen. NaNO2 had a very limited effect on the growth of lactic acid bacteria at 50 and 100 mg/l but at 400 mg/l a more pronounced inhibitory effect was found. Bacterial growth was enhanced by 1-2% (w/v) of added NaCl, while NaCl concentrations above 3% (w/v) had a clear inhibitory effect. Leuconostoc isolates seemed to be more sensitive to sodium nitrite and sodium chloride than homofermentative lactobacilli strains. Among homofermentative lactobacilli, the strains resembling Lactobacillus curvatus were more sensitive to NaCl than those resembling Lactobacillus sake.     

D-Dimer Improves the Prognostic Value of Combined Clinical and Laboratory Data in Equine Gastrointestinal Colic

The discriminating ability of 15 parameters alone or in combinations, including results from analysis of plasma endotoxin, the Nycomed plasma D-Dimer test and phospholipase A₂, were analyzed to predict morbidity and mortality in equine gastrointestinal colic. Endotoxaemia was a characteristic feature of the colic horses. The problem of adequately predicting non-survivors among colic horses required several parameters to be included in the logistic model: if the “classical parameters”, (heart rate, respiratory rate, PCV, anion gap) were included in the model, addition of plasma D-dimer, phospholipase A₂, and Cl^- significantly improved the predictive value of the logistic model. Increasing heart rate and D-dimer together with decreasing chloride was a risk factor for nonsurvival. The sensitivity of this three-parameter logistic model to predict nonsurvival was 78% and specificity 77%. The Nycomed D-Dimer test is recommended as a horse-site test to predict disseminated intravascular coagulation and nonsurvival in equine colic.     

RPLC法测定饲料添加剂中的B族维生素

本文提出了利用反相离子对色谱法,简单,快速,准确同时定量测定饲料添加剂中的烟酸,烟酰胺,盐酸吡哆辛,氰钴胺素,核黄素和硫胺素。样品前处理简单,六个维生素能在12min内获得满意的分离,各组份之间的分离度Rs大于1.60。各个维生素的回收率在87.0～101.0％,相对偏差为3.1～2.0％。色谱柱为LichrosorbRP-18 250×φ5mm,流动相为甲醇/水,0.25％TEA,1.25mmol/l PICB-5,3.75mmol/l PICB-7,pH3.00,紫外可变波长检测器采用MAXPL操作方式λ 1=254nm,λ_2=280nm,λ_3=354nm,流速1.1 nl/min。     

SS-1型声速实验仪的研制

本文阐述了SS—1型声速实验仪的原理、结构和测量方法。波动学和分子物理学是物理学中的重要组成部分,"声速的测量"和"Y值的测量"两个实验有助于学生对波动相位的空间分布、谐振动的合成、李萨育图、能量按自由度均分原