红外分光光度法测定处理后油气田含油污泥中石油类

建立了红外分光光度法测定油气田含油污泥中石油类的方法,并对方法中提取频率和时间、提取次数、硅酸镁吸附方式及填充高度、空白试验的制备进行优化。实验结果表明,方法检出限为0.02 mg/g,空白加标样品测定的精密度在2.2%~8.9%之间,加标回收率在92.5%~100%之间;实际样品测定相对标准偏差在2.4%~8.9%之间,加标回收率在88.2%~104%之间。本方法前处理操作简单,样品用量较少,测定结果的准确度和精密度较好,检出限低,可适用于处理后油气田含油污泥中石油类的准确测定。     

微波消解ICP-MS法测定植物样品中的镉

用电感耦合等离子质谱法测定植物样品中的痕量镉,用微波消解和电热板消解分别测定植物样品中镉的含量。采用微波消解的方法,向植物样品中分别添加一定浓度的的镉,3个植物样品的回收率在93.6%～97.4%之间,方法的检出限分别为0.007μg/g。而采用电热板消解,回收率则在90.1%～92.9%之间,方法的检出限为0.010μg/g。通过对比,微波消解前处理,镉回收率较高,检出限更适合植物样品中痕量镉的测定需求。     

原子荧光光谱法测定植物样品中痕量镉的含量

建立微波消解-原子荧光光谱法测定植物样品中的镉含量的方法。用微波消解仪器对植物样品进行消解,在最佳仪器反应条件下,测定植物样品中镉的含量。镉浓度为0.1~0.8 ng/mL时荧光强度与镉浓度呈显著的线性关系,r=0.9995,方法的检出限为0.0018 ng/mL。向植物样品中分别添加一定浓度的镉,3个样品的回收率在90.4%~92.1%之间。方法的精密度为1.64%。该方法简便、快速,有较高的灵敏度、准确度、精密度和较低的检出限,适合植物样品中镉含量的测定。     

连续流动分析法测定水中高锰酸盐指数

报道了用连续流动分析法测定水样品中的高锰酸盐指数的方法,并对影响测定的基体因素进行了初步的探讨,实验确定了最佳优化测定条件。样品的标准加入回收率是94.0%～102%、相对标准偏差小于2%.该方法准确、快速、简便,线性范围大,灵敏度高。应用于水源水、出厂水、饮用净水中高锰酸盐指数的测定,结果满意。     

对植物油中缩水甘油酯的两种气相色谱质谱测定方法的比较分析

目的:对两种间接测定植物油中缩水甘油酯(GEs)的方法进行比较。方法:通过对操作步骤、方法学参数及样品测定结果进行测定计算对两种检测方法进行比较。结果:两种方法操作步骤各有特点;检测结果相对标准偏差小于等于10%,回收率范围在58.5%~102.9%;使用FAPAS质控样品T2649QC进行测定,结果在允许范围之内;氯代法的结果比溴代法的测定结果高,相对标准偏差大;两种方法测定结果 P<0.05,有统计学差异。结论:氯代法适用于有熟练实验操作人员、需要快速进行测定的样品;溴代法则适用于大量样品GEs的一次性测定。两种方法分情况使用,以满足不同类型的检测需求。     

流动注射法测定饮用水中氰化物

目的建立测定水中氰化物的流动注射分析法。方法一般样品直接进样,如果样品中含有游离余氯时先用无水亚硫酸钠溶液除氯后再测定。应用FIA6000型全自动流动注射分析仪直接在线蒸馏测定饮用水中氰化物。结果该测定方法相关性好,相关系数为0.9999,线性范围宽2.0～90.0μg/L,精密度RSD为1.95%～2.30%,方法检出限为0.156μg/L。结论方法简便、快速,干扰少,灵敏度高,有较高的实用价值,特别适合大批样品的测定。     

超声波提取法测定土壤中的六六六、滴滴涕

文章采用超声波提取,毛细管柱气相色谱法分析测定土壤中的六六六、滴滴涕,检出限低,相对标准偏差为7.4%～1 2 .7% ,加标回收率为86.2 %～1 0 0 .6%。该方法简便快速,便于多个样品直接提取,特别适合大批量样品的测定。     

应用ICP-MS测定国际比对果汁样品中铅、镉和锡的含量

建立了微波消解、电感耦合等离子体质谱法（ICP-MS）同时测定国际比对果汁样品中铅、镉和锡的方法。应用微波消解进行样品前处理,采用在线内标校正基体干扰,采用干扰方程抑制质谱干扰,使用工作曲线计算出样品中铅、镉和锡元素的含量。测定结果表明,铅、镉和锡元素的检出限分别为0.021、0.016和0.052μg/L,相对标准偏差（RSD〈5%）,加标回收率介于90%～105%,用该方法测定FAPAS国际比对果汁样品,反馈的统计结果显示铅、镉和锡元素的Z值分别为-0.4、0.1和-0.2,结果均为满意。该方法快速、简单、精确,适于果汁中铅、镉和锡的测定。     

ICP-MS同时测定地质样品中的锆和铪

研究了运用ICP-MS测定矿石样品中锆、铪含量的方法;采用过氧化钠熔融,用高纯水提取,过滤,用1＋1 HCl溶解沉淀;确定了仪器最佳工作条件,选择了合适的内标校正锆、铪。该方法测定锆、铪的检出限分别为0.03ng/g、0.003ng/g,精密度分别为2.88%、3.05%,回收率为96.1%-103%。使用该方法分析标准参考物质和实际样品,分析结果与认定值和其它分析方法测定值一致,此法方便,快捷,适用于大量地质样品中锆、铪的直接检测。     

电感耦合等离子体发射光谱法(ICP-AES)测定矿石中钼

本文报道了电感耦合等离子体发射光谱(ICP-AES)快速测定矿石中钼的方法 ,为了消除矿石的基体干扰,溶解国家一级标准样品制备成标准系列的标准溶液,制作校准曲线。钼的测定波长为202.030nm。本法检出限为0.094μg/mL,实际测定矿石中大于0.005%以上的钼。相对标准偏差(RSD)的范围:0.12%～1.4%。标样测定结果与国家标准样品值结果一致,矿石样品测定值与分光光度法测定结果一致。     

利用长波红外偏振成像与光强图像融合的实验研究

为解决红外迷彩对传统热成像系统的干扰问题,达到在战场上识别红外伪装目标的目的,进行了长波红外偏振成像与光强图像融合的实验研究。采集了典型战场背景的长波红外偏振图像,利用MATLAB编程对红外偏振图像处理得到了长波红外偏振度图像,进一步对偏振度图像和光强图像进行了融合。实验结果表明,红外偏振度图像比原始红外图像的灰度均值提高了53%,灰度标准差提高了90%,平均梯度提高了2.04倍;融合后的图像比红外偏振度图像的灰度均值提高了15%,灰度标准差提高了4%,平均梯度提高了17%。     

中国成为汽车产销大国(英文)

<正>While global economy is still moving difficultlyto wards recovery, China has become a major auto consumption market in the world. According to statistics released by the China Association of Automobile Manufacturers ( CAAM) , China's output and sales     

Start up and steady state friction of alumina against alumina

Using a pin-on-disc testing machine, the authors investigated the start up and steady state friction of highly polished alumina against itself and studied the factors affecting the friction. The lubricants used in this paper were 1 wt.% water solution of carboxymethyl cellulose sodium salt (CMC-Na 1 wt.% water solution) and distilled water. It is observed that many factors, such as lubricants, load, sliding velocity, resting time and start up acceleration etc., have an influence on the friction of alumina.against alumina. The experimental results indicate that the coefficients of the start up and steady state friction when CMC-Na 1 wt.% water solution is the lubricant are much smaller than when distilled water us used, and it is possible that alumina-on-alumina hip joints may enjoy full fluid film lubrication with good machining, good fit and a proper lubricant.     

球化孕育处理工艺对下贝氏体铸铁组织特性及力学性能的影响

采用真空中频感应炉,通过改变球化孕育处理工艺获得具有不同形态石墨的铸造试样,将铸件加热到860 ℃保温2 h,使用20 ℃的硝酸钠、亚硝酸钠饱和溶液将其连续冷却至室温,并在250 ℃低温回火2 h后空冷,获得具有不同形态石墨的下贝氏体基体组织。研究了球化孕育处理工艺对石墨球化效果的影响,以及石墨形态对热处理显微组织和力学性能的影响。结果表明：球化处理温度及时间对铸铁中的镁吸收率有显著影响,超过1 500 ℃时,镁烧损加剧,当球化处理温度为1 450 ℃,镁吸收率达到64.2%;孕育剂添加工艺也是影响铸铁中石墨的形态和分布的重要因素,当一次孕育和二次孕育添加量分别为0.8%和1.2%时,石墨的形态以球状为主,尺寸细小且分布均匀,石墨的球化率为93%,球化级别达到2级,尺寸级别为9级;另外,均匀分布的球状石墨有利于提高热处理后下贝氏体铸铁的综合力学性能。     

Application of two forms of silicon and their impact on the postharvest and the content of bioactive compounds in cucumber (<i>Cucumis sativus</i> L.) fruits

The metabolic activity of the fruits continues even after harvest, which results in the loss of bioactive compounds, a decrease in the quality of the fruits, softening and browning, among other negative effects. The use of certain elements such as silicon can improve postharvest quality, since it is involved in the metabolic, physiological and structural activity of plants, moreover can increase the quality of the fruits. In addition, nanotechnology has had a positive impact on crop yield, nutritional value, fruit quality and can improve antioxidant activity. For these reasons, the use of beneficial elements such as silicon in the form of nanoparticles can be a viable option to improve the characteristics of the fruits. In the present study was evaluated the application of potassium silicate (125, 250 and 500 mg L⁻¹) and SiO₂ nanoparticles (125, 250 and 500 mg L⁻¹) during the development of the crop. The results showed that the application of silicon (potassium silicate and silicon nanoparticles) increased the content of total soluble solids (up to 15.6% higher than control), titratable acidity (up to 38.8% higher than control), vitamin C (up to 78.2% higher than control), phenols (up to 22% higher than control), flavonoids (up to 64.6% higher than control), and antioxidant activity in lipophilic compounds (up to 56.2% higher than control). This study suggests that the use of silicon can be a good option to increase the content of bioactive compounds in cucumber fruits when they are applied during the development of the crop.     

Materials and techniques for pressure calibration by resistance-jump transitions up to 500 kilobars

The resistance jump of alpha-->epsilon transitions for Fe-V alloys up to 20-wt. % V is observed by static compression. It is used along with alpha-->epsilon transitions for Fe-Co alloys and some other transitions as the basis for pressure calibration up to 500 kilobar.     

Performance of R290 and R1270 for R22 applications with evaporator and condenser temperature variation

In this study, therma l performance of two hydrocarbon refrigerants of R290 and R1270 was measured in an attempt to substitute R22. They wer tested in a heat pump bench tester of 1 ton capacity with a hermetic rotary compressor. Water and water/glycol mixture were employed as the secondary heat transfer fluids in the test bench. All tests were conducted under the same external conditions simulating three different air-conditioning and heat pumping conditions. Test results show that the coefficient of performance of these hydrocarbon refrigerants is up to 11.5% higher than that of R22 under all conditions. Refrigeration capacity of R290 is up to 8.2% lower than that of R22 under normal air-conditioning and heat pumping conditions. Under extremely cold temperature conditions, however, the capacity of R290 is 5% higher than that of R22. On the other hand, the capacity of R1270 is similar to that of R22 under all conditions. Compressor discharge temperatures of these hydrocarbons are reduced by 14–31°C as compared to R22. The amount of charge is reduced up to 58% as compared to R22. Overall, these hydrocarbons provide good performance with reasonable energy savings without any environmental problems and thus can be used as long-term alternatives for residential air-conditioning and heat pumping applications.     

轨道车的电液混合功率迁移与耦合特性

针对现有电力轨道车存在起步性能差、功率冲击大及续航里程短等缺点,研发了一套新型的电液混合驱动系统。建立了系统功率流的数学模型,分析并确定了电功率和液压储能功率之间的耦合方法。基于典型坡道下的行驶工况,制定了适用于不同行驶阶段的功率耦合策略,并利用AMESim软件进行仿真分析。结果表明：起步阶段,电液混合驱动系统可改善轨道车起步加速性能高达57%,并节约了61.7%的电耗;加速阶段,电液混合驱动系统可基本消除电功率冲击,并节约了50%的电耗。     

化学合成尿囊素及应用的研究

论述了尿囊素的性质及应用，研究了利用乙醛酸直接合成尿囊素的工艺条件，实验表明：尿囊素的产率68.6%，纯度为99.6%，达到以了国家药典及相关标准要求。     

室温辐射探测器用CdZnTe晶体生长及其器件制备

采用改进的垂直布里奇曼法生长了直径为60 mm的碲锌镉晶体,晶体利用率达到70%以上。晶体中Te沉淀/夹杂密度小于1×10-3cm2,电阻率达到4×1010Ω.cm。利用得到的晶体制备了平面型单元探测器,测量了对不同能量射线的分辨率,其中对241Amγ能谱的分辨率达到4.7%,对137Cs能谱的分辨率为4.2%。采用Hecht公式对探测器收集效率与偏压的关系进行了拟合,得到电子的迁移率与寿命乘积值达到2.3×10-3cm2/V。