想想"地主"看看太阳

每当太阳从东方升起,在地球上生存的每一个人,又都会开始新一天的生活。“眼睛一闭一睁,一天过去了;眼睛一闭不睁,一辈子过去了”,噢,人生真是苦短啊! 说起人生之苦和世道之难,感叹不已。今年不知怎么搞的,苦和难好像一个个排着队涌来。核弹竞赛真来了,恐怖袭击加剧了,飞机空难重演了,地震频率加快了,山体滑坡厉害了。暴风骤雨更猛了,能源争夺空前了,空气污染天昏了,股市行情难猜了,房价居高不下了,今年夏天热坏了,就连酒后驾车的人也多多了。嘿,怎一个“了”字能了得？     

新型油罐液位自动控制系统原理分析及PID校正

通过分析油罐内油品液位对油品质量和安全的影响,介绍了一种新型液位自动控制系统及其工作原理,建立了系统的数学模型,绘制了系统的结构图,对系统状态进行了选择,对系统性能进行了分析,通过PID控制器对系统进行校正,改进了系统的稳态和动态性能.     

甲醇回收精镏塔的微机优化控制

本文以某农药厂甲醇回收精馏塔为实际对象,进行了稳态优化控制方案的开发.首先建立了精馏塔稳态机理模型,在此基础上建立了控制模型和进料成分估计模型,进而设计了优化控制方案,实现了SPC控制.方案实施后,提高了甲醇收率,降低了能耗,获得了可喜的经济效益.     

抽油杆修复技术的改进与应用

为解决原有抽油杆修复技术存在的弊端,提出了抽油杆修复技术的改进方法。改进后的修复线可以拆除扶正器,提高了修复率,增加了抽油杆材质分选工序,降低了修复成本;可以安装扶正器,杜绝了抽油杆偏磨;采用常温低压清水清洗技术,增加了表面除锈工序和淬火前的探伤工序;采用机械化的拧扣工序,提高了抽油杆的淬火综合性能,实现了杆头过渡段自动探伤和抽油杆防腐的自动化,降低了工人劳动强度,提高了经济效益。     

天然气管道设备静密封与无泄漏管理

介绍了静密封技术的基本知识,对泄漏量进行了计算与分析,总结了提高管道、阀门、设备密封水平的不少经验,提出了一些合理化建议,编制了管道设备静密封无泄漏管理文件,分析了典型密封案例,静密封与无泄漏管理技术与经验值得天然气企业借鉴与推广.     

重油催化裂化装置回炼柴油生产高辛烷值汽油的工业应用

介绍了中国石油四川石化公司2.5 Mt/a重油催化裂化装置回炼渣油加氢柴油以增产高辛烷值汽油的工业应用。应用结果表明:50.39%的柴油转化为高辛烷值汽油;回炼渣油柴油后,汽油收率增加了1.39个百分点,柴油收率增加了1.32个百分点,液化气收率增加了1.02个百分点,回炼油收率减少了1.34个百分点,油浆收率减少了0.92个百分点,焦炭收率减少了1.57个百分点,总液体收率增加了2.39个百分点,汽油辛烷值增加了0.9个单位,柴油十六烷值降低了2.0个单位。     

斜井抽油杆柱组合设计方法研究

建立了斜井抽油杆柱载荷计算数学模型,给出了计算方法．按照修正的美国石油学会抽油杆柱设计方法,研究了斜井抽油杆柱等强度设计方法,给出了设计步骤,编制了相应的计算机软件,为工程人员提供了方便快捷的设计工具．     

动植物油在催化裂化装置上的掺炼应用

在实验室及工业规模的两段提升管催化裂化装置上,以胜华减压蜡油(VGO)为主要裂化原料,进行了可再生动植物油的掺炼裂化反应研究.结果表明,与胜华VGO单一裂化相比,掺炼质量分数为22.3%的动植物油后,液化气(LPG)收率上升了0.45个百分点,LPG中丙烯的质量分数提高了1.88个百分点,汽油收率保持不变;同时,裂化所得稳定汽油的诱导期至少上升28.2%,胶质下降了30.4%,烯烃体积分数下降了11.1%,含硫质量分数下降了25.0%;裂化所得轻柴油的闪点升高了9.9%,冷滤点下降了71.4%,残炭质量分数降低了59.1%,含水质量分数下降了83.3%,含硫质量分数降低了18.5%.     

塞平一井分段试油压裂工艺技术研究

长庆石油勘探局在安塞油田塞平一井分段试油压裂工艺技术研究中,自行设计研制了水平井自定位定向射初装置,进行了裂缝数目和工艺参数优选,并研制了液体胶塞技术,成功地实现了井筒隔离,保证了该井分4段射孔、试油压裂施工的顺利进行,取得了明显的增产效果。此项技术研究和实践的成功,填补了我国水平井分段试油压裂工艺技术的空白,为特低渗透油层水平井的开发提供了宝贵的经验。     

水源井数字化建设在合水油区的应用与优化

文章介绍了水源井数字化建设的主要设备及其功能。在合水油区的应用中,水源井的数字化管理实现了现场设备无人值守,大大降低了工人的劳动强度,稳定了产水量,降低了水源井的故障率,延长了设备使用时间,达到了节能节电效果。针对水源井数字化建设存在不能监测到水位的不足之处,安装了水源井水位监测系统,同时与水源井自动控制仪并接起来,并将采集的水源井水位数据在站控电脑上显示,完善了数字化功能,优化了系统。     

Clothianidin dissipation in tomato and soil, and distribution in tomato peel and flesh

Clothianidin, a new neonicotinoid insecticide, was systematically evaluated. An analytical method using gas chromatography with electron capture detection was developed. Recoveries were between 92% and 102%, with relative standard deviations from 3% to 5% at three fortified levels. The decrease of clothianidin in tomato and soil samples under field conditions at Beijing, Shandong, and Anhui were determined. The dissipation rates of clothianidin fit first-order kinetics. Its half-lives ranged from 6.7 to 12.7 days in soil, and 7.0 to 11.9 days in tomato. On the suggested pre-harvest interval of 7 days, the distribution of clothianidin in tomato peel and flesh was studied. Most residues were found on the peel. Hence, removing the tomato peel before consumption is advisable. The stability of clothianidin fortified at 0.3 or 3 mg/kg in frozen green and red ripe tomatoes was also determined. The half-life mainly depended on the spiked levels of this pesticide.     

中国致密砂岩气及在勘探开发上的重要意义

致密砂岩气藏系指聚集工业天然气的致密砂岩场晕或圈闭,根据其储集层特征、储量大小及所处区域构造位置高低,可将致密砂岩气藏分为两类:"连续型"致密砂岩气藏和"圈闭型"致密砂岩气藏,前者通常位于构造低部位,圈闭界限模糊,无统一气水界面,往往气水倒置,储源一体或近源;后者位于圈闭高处,上气下水,储量规模较小但产量相对较高。中国致密砂岩气都是煤成气,组分以烷烃气(C1 4)为主,甲烷含量最高,烷烃气具正碳同位素系列;非烃气(主要是CO2和N2)含量低。截至2010年底,中国致密砂岩气的储量和年产量分别占全国天然气储量和产量的39.2%和24.6%,预计将来比例还会提高。与页岩气、煤层气等非常规气相比,中国近期在非常规气勘探开发中应以致密砂岩气为先。     

Aflatoxins and fumonisins in rice and maize staple cereals in Northern Vietnam and dietary exposure in different ethnic groups

Mycotoxins in food are increasingly a food safety hazard concern in particular in developing countries. This study was performed to determine the occurrence and determinants of aflatoxin and fumonisin contamination in rice and maize and to assess health risks through dietary intake exposure among ethnic minority groups in northern Vietnam. A total of 111 rice and 102 maize samples, were tested for occurrence of fungi and mycotoxins, i.e. aflatoxins (AF’s) and fuminisin B (FB). Results showed that 107 (96.4%) rice and 84 (82.4%) maize samples were contaminated by fungi. Aspergillus flavus was found in 68 (61.3%) rice and 30 (29.4%) maize samples, Aspergilus parasiticus in 40 (36.0%) rice and 27 (26.7%) maize samples. AF’s - were detected in 27 rice (24.3%) and 27 maize samples (26.4%) at minimum and maximum levels in rice of 2.06 and 77.8 ng/g and 20.5 and 110 ng/g in maize, respectively. Nine (8.1%) rice and 24 (23.5%) maize samples contained FB at ranges of 2.3–624 ng/g in rice and 5.6–89.8 ng/g in maize. Data collected through interviews and observations in households showed that type of crop, storage duration and presence of fungi, particularly mycotoxigenic fungi were important risk factors for AF’s and FB contamination. Based on daily food consumption data, the estimated average exposure dose of aflatoxin B₁(AFB₁) from rice was 21.7 ng/kg bw/day for adults and 33.7 ng/kg bw/day for children. For FB, the rice based average exposure amounted to 536 ng/kg bw/day for adults and 1019 ng/kg bw/day for children. The calculated excess risk of liver cancer incidence by ingestion of cereals containing AFB₁ was 1.5 per 100,000 adults and 2.3 per 100,000 children per year. The average intake of FB was calculated to be lower than the tolerable diet intake (TDI). Our findings highlight that rice and maize are contaminated with mycotoxins at levels representing actual health hazards for the ethnic minority groups consuming these stable cereals. Proper drying and storage conditions in households are likely to reduce the mycotoxin contamination.     

改进中加强 创新中发展——改革开放30年企业思想政治工作的实践与探索

改革开放30年来，企业思想政治工作随着形势的不断变化，曾经面临着诸多新问题。企业思想政治工作正是在解决这些问题的实践中不断探索，创新思路和方法，提升效果和水平，成为企业改革、发展、进步的动力源泉。     

Aflatoxin M1 in raw and UHT cow milk collected in Bosnia and Herzegovina and Croatia

Aflatoxin M1 (AFM1) concentrations were determined in raw and UHT cow milk samples collected in different regions of Bosnia and Herzegovina and Croatia during the autumn months of 2014. The mean AFM1 levels in the raw milk samples were (ng/kg): 6.22 in Bosnia and Herzegovina, 5.65 in Croatia. In all except one milk sample, AMF1 levels were below the LOQ value of 34.2 ng/kg (ELISA method). In four milk samples, AFM1 concentrations exceeded the EU MRL of 50 ng/kg. Samples were subjected to LC-MS/MS analysis which confirmed elevated values determined by ELISA. Elevated levels were in the range 56.6–132.6 ng/kg. Two positive milk samples from Bosnia and Herzegovina originated from Una Sana Canton, two from Croatia from eastern Croatia. The highest AFM1 levels of 132.6 ng/kg was measured in milk from eastern Croatia. In 214 samples of processed UHT milk from Bosnia and Herzegovina and Croatia, AFM1 ranged from 2.29 ng/kg to 21.4 ng/kg, all below the LOQ value. AFM1 exceeded the EU MRL value in only 0.62% of milk samples, indicating the sporadic use of contaminated feedstuff at farms in both countries.     

Steady and Great Strides in Stable Production and Increased Efficiency in Daqing Oilfield

<正>Daqing Oilfield is the largest oilfield in China.Its current troubles reflect a greater reality in the country:once a major oil exporter,China is now one of the world's largest net oil importers.The development costs of aging oilfields within China,including the Daqing Oilfield,are on the rise.Thus,it is often more cost-effective to purchase oil from other places of the world to meet the rising demand for oil within     

Aflatoxins in bulk and pre-packed pistachios sold in Spain and effect of roasting

The occurrence of aflatoxins in national and imported pistachios available in Aragón (NE Spain), purchased from commercial outlets during 2007, was surveyed. Thirty-two samples of roasted pistachios were analyzed for aflatoxins by immunoaffinity cleanup with liquid chromatography and fluorescence detection using post-column photochemical derivatization. Results showed that the incidence of aflatoxin B₁ and B₂ in pre-packed pistachios was 19% and 6%, while in bulk pistachios was 50% and 12.5%, respectively. All positive samples originated from Iran, while pistachios from USA, Turkey and Spain tested negative for aflatoxins. The low degree of contamination ranged from 0.12 to 0.29 μg/kg, and no sample exceeded the maximum permitted level for aflatoxins in pistachio nuts. Naturally occurring aflatoxin B₁ was not noticeably reduced by commercial roasting at 120 °C for 20 min.