Determination of ephedrine and codeine in human urine by cation-selective exhaustive injection and sweeping micellar electrokinetic chromatography

为在由毛状的电气泳动(CE ) 的人的尿的麻黄素和 codeine 的决心的一个敏感方法被描述。为了改进敏感，包括阳离子选择的彻底的注射(CSEI ) 的二种联机集中技术和大规模 micellar 电镀物品，运动层析(sweeping-MEKC ) 被使用。在最佳条件下面，察觉限制(S/N = 3 ) 是 0.10 &#x3bc；为麻黄素和 0.80 &#x3bc 的 g/L；为 codeine 的 g/L。这个方法成功地被用于真实的尿样品分析。

Injection Strategy in Natural Gas–Diesel Dual-Fuel Premixed Charge Compression Ignition Combustion under Low Load Conditions

Dual-fuel premixed charge compression ignition (DF-PCCI) combustion has been proven to be a viable alternative to conventional diesel combustion in heavy-duty compression ignition engines due to its low nitrogen oxides (NOx) and particulate matter (PM) emissions. When natural gas (NG) is applied to a DF-PCCI engine, its low reactivity reduces the maximum pressure rise rate under high loads. However, the NG–diesel DF-PCCI engine suffers from low combustion efficiency under low loads. In this study, an injection strategy of fuel supply (NG and diesel) in a DF-PCCI engine was investigated in order to reduce both the fuel consumption and hydrocarbon (HC) and carbon monoxide (CO) emissions under low load conditions. A variation in the NG substitution and diesel start of energizing (SOE) was found to effectively control the formation of the fuel–air mixture. A double injection strategy of diesel was implemented to adjust the local reactivity of the mixture. Retardation of the diesel pilot SOE and a low fraction of the diesel pilot injection quantity were favorable for reducing the combustion loss. The introduction of exhaust gas recirculation (EGR) improved the fuel economy and reduced the NOx and PM emissions below Euro VI regulations by retarding the combustion phasing. The combination of an NG substitution of 40%, the double injection strategy of diesel, and a moderate EGR rate effectively improved the combustion efficiency and indicated efficiency, and reduced the HC and CO emissions under low load conditions.

Influence of Diesel Engine Intake Throttle and Late Post Injection Process on the Rise of Temperature in the Diesel Oxidation Catalyst

In order to effectively implement DPF(Diesel Particulate Filters)regeneration control,thermal management of exhaust products before and inside Diesel Oxidation Catalyst(DOC)is necessary.In the present study,the Influence of the intake throttle valve and late post injection process on temperature rise inside DOC is analyzed through engine bench tests.The steady experiment results show that adjustment of the intake throttle valve can effectively increase exhaust temperature before DOC;in particular,with intake throttle valve opening at 20%,temperature before DOC can be increased by about 170℃ with respect to the full opening.An increase in the late post injection quantity can produce a significant rise of the temperature inside DOC,however its impact on the exhaust temperature before DOC is relatively limited.As the late post injection quantity increases,Hydrocarbon(HC)emissions also grow;in the present work it is shown that with a proper injection quantity,a considerable temperature increase inside the DOC can be obtained with relatively low HC emission.More specifically,with the intake throttle valve at 30%and DOC reaching ignition temperature as the late post injection quantity is increased,the exhaust temperature after DOC can be made larger than 550℃,adequate for DPF active regeneration.

国Ⅵ直喷汽油机颗粒数量及微观形貌排气输运演变特性

开展了某一国Ⅵ直喷汽油机三元催化转化器(TWC)前、TWC后、汽油机颗粒捕集器(GPF)后3个位置的颗粒物采样及微观形貌研究,分析了发动机工况、TWC、GPF对国Ⅵ直喷汽油机尾气颗粒数量、粒径分布、微观形貌的影响。结果表明,该直喷汽油机尾气颗粒数量排放整体上呈单峰分布,低转速小负荷工况下,粒径<23nm的颗粒数量较高。随着发动机转速和负荷的增大,峰值粒径向大粒径方向移动。直喷汽油机尾气颗粒物由“核‒壳”结构基本碳粒子堆积形成,呈链状、枝状、簇状等结构;负荷增大,颗粒物尺寸略有增大,基本碳粒子重叠度增强,分形维数增大;转速增大,颗粒物尺寸减小,基本碳粒子重叠度减弱,分形维数减小。随着排气输运的进行,颗粒数量逐渐降低;TWC不影响颗粒的粒径分布形态,颗粒数量净化效率41.6%~94.2%,对<23 nm的小粒径颗粒净化效果较好,低转速小负荷工况的颗粒数量净化效率较高;GPF的颗粒数量净化效率约80%,23~100 nm颗粒数量净化效率较高,对粒径<10nm的颗粒净化作用不大。TWC和GPF不影响颗粒物结构形式,TWC和GPF后颗粒物基本碳粒子重叠度减弱,分形维数减小。

液压排气阀特种卡帽注射模具设计与CAE分析

介绍了一种液压排气阀特种卡帽,内部采用异型卡位设计,外侧采用长尾柄结构,既有利于按压排气、也可以快速旋转,采用聚甲醛(poly for maldehyde, POM)材料,能保持较高的热稳定性和抗老化性能。在制造过程中,设计了一种全新的一模两腔的热流道哈弗块侧抽芯模具结构,经CAE分析产品的细节特征,在哈弗块上设置了隔水板冷却水路,内部型芯也设置了隔水板水路,提高了模具冷却效率,运用CAE软件模拟了产品的填充与冷却过程。经试模验证,该模具结构紧凑,塑件质量稳定、精度高,开合模动作合理可靠,制品顺利脱模,可有效节约成本,缩短了产品成型周期,提高了产品的生产率,产品能完全达到客户要求,为同类型产品提供了良好的解决方案。

不同注气成分置驱瓦斯效果数值模拟研究

注气促抽瓦斯的注气成分主要有N_(2),CO_(2)和空气,但目前针对不同注入成分的置驱效果对比研究较少。针对该问题,建立了考虑裂隙气体渗流和基质孔隙气体扩散的注气成分置驱瓦斯数学模型,在对该模型验证的基础上,模拟注入气体置驱煤样瓦斯气体过程,并对比研究相同注气压力和煤体渗透率条件下不同注气成分(N_(2),CO_(2)和空气)对瓦斯的置驱效果。结果表明:①相同注气时间下,从注气端到排气端,注入气体的体积分数逐渐降低,在注气端附近注入气体的体积分数最高;瓦斯体积分数逐渐增加,在排气端附近瓦斯体积分数最高;随着注气时间增加,注入气体的体积分数增加区域逐渐向排气端移动直至覆盖整个煤样,瓦斯体积分数降低区域也逐渐向排气端移动直至覆盖整个煤样,表明煤样中的瓦斯逐渐被置换出来,进而被驱替出整个煤样。②在相同注气时间内,从注气端到排气端,N_(2),CO_(2)和空气3种注入气体体积分数和瓦斯体积分数具有相似的变化规律,即从注气端到排气端,注入气体体积分数逐渐降低、瓦斯体积分数逐渐升高,随着注气时间增加,注入气体的体积分数增高区域增加。相同注气时间、煤样相同位置处注入气体的体积分数和瓦斯体积分数互补,即相加为100%。③3种注入气体对瓦斯的置驱效果排序为CO_(2)>空气>N_(2)。④对排气端气体的体积分数分析可知,排气端气体的体积分数随时间变化可分为突破阶段、平衡进行阶段和置驱完成阶段。不同注入气体3个阶段持续时间不同,注入N_(2)突破时间和置驱完成时间分别为30,90 min;注入CO_(2)突破时间和置驱完成时间分别为20,80 min;注入空气突破时间和置驱完成时间分别为28,87 min。⑤在现场应用时,应根据具体煤层的吸附解吸能力、煤层自燃特性等选择合适的注入气体。

基于CFD的垃圾焚烧锅炉二次风喷入角度优化研究

为研究二次风喷入角度对焚烧锅炉炉膛内温度、烟气速度、烟气停留时间、排烟热损失的影响以及二次风喷入角度与焚烧炉出口处NO_(x)浓度的关联性,采用UDF编译边界条件和Fluent耦合的方法,针对某600 t/d城市生活垃圾焚烧锅炉的前后墙二次风喷入角度进行数值模拟。模拟的前墙二次风喷入角度变化为68°~80°,后墙二次风喷入角度变化为61°~73°,二次风风速为42 m/s,二次风温度为301.15 K。结果表明:后墙二次风喷入角度不变时,随着前墙二次风喷入角度增加,NO_(x)浓度先升高后下降(最低为142.23 mg/m^(3),且焚烧炉排烟热损失降低(最小为7.12%);前墙二次风喷入角度不变时,随着后墙二次风喷入角度增加,NO_(x)浓度也呈现先升高后下降的趋势(最低为149.15 mg/m^(3),且焚烧炉排烟热损失先升高后降低(最小为7.46%);前后墙二次风喷入角度分别为80°和67°时,SNCR两层喷枪之间的平均温度为1229.59 K,停留时间为1.63 s,与其他工况相比更加接近SNCR脱硝的最佳反应温度和停留时间,第一烟道出口处的平均温度为1211.36 K且停留时间大于2 s,有助于抑制二噁英的生成。

针对某车尿素喷嘴喷射量变小问题的分析与改进

商用车国六产品投放初期,某主机厂重型车辆出现尿素喷嘴喷射量变小问题,造成发动机排气后处理系统故障灯常亮,通过拆检尿素喷嘴,发现其内部存在堵塞物。本文针对该问题提出了排气后处理系统优化改进方案,通过拆检尿素喷嘴结构、取样尿素液样品分析、尿素溶液浸泡铝板以及拆检尿素箱进行电镜分析等方法,发现尿素喷嘴喷孔内壁均可见黑色、黑褐色沉积物,其主要为含铝的氧化物以及与其他成分混合,最后对优化改进后的车辆进行了跟踪验证。试验结果表明,车辆未再出现上述现象,验证了改进措施的可行性,对日后实际设计工作具有一定借鉴意义。

后喷策略对柴油机低负荷点排气温度及燃烧影响

以某高压共轨重型柴油机为研究对象,利用converge软件建立了缸内燃烧数值模型,通过采集台架试验数据验证了模型的准确性,分析了单次后喷正时和喷油量对排气温度和缸内燃烧的影响规律。以排气温度为指标,基于单次后喷最优结果,提出并优化了双次后喷策略,分析了双次后喷对缸内燃烧的影响机理。结果表明,单次后喷喷油量一定时,排气温度随单次后喷正时增大呈先增大后减小趋势,单次后喷正时25°CA时,排气温度最高,相比无后喷工况排气温度提高146.2℃。在单次后喷基础上,优化双次后喷喷油量组合和双次后喷间隔。结果表明,在后喷油量相同时,双次后喷相比单次后喷可有效提高排气温度,且排放水平相当。第一次喷油量50%、第二次喷油量50%、间隔10°CA时,排气温度提高19.3℃。

航空发动机试车台多方位排气引射系统设计与分析

航空发动机试车台是对航空发动机进行综合试验研究和生产试车的重要设备,试车台排气系统可将发动机产生的高温、高速燃气排入大气中。为解决航空发动机试车台多方位排气引射系统排气不畅的问题,采用Fluent软件对改造设计的排气引射系统进行建模和气动分析,通过气动分析验证排气引射系统设计的可行性,对该发动机其他型号排气引射系统的研制以及其他多方位排气引射系统的应用具有理论指导作用和实际意义。

可换镶件多功能教学注射模设计

随着汽车工业的快速发展,现在国内模具领域技术人才短缺的局面,各个企业、职业院校都在不断的研究模具技术人才的培养模式,以加快模具人才的输出,解决模具技能人才供应不足的难题。本副可换镶件多功能教学模具是基于德国双元制模具制造专业企业学徒和学生而量身定制设计的,针对各大模具制造企业和各高校模具制造与设计专业没有合适的教学模具,结合模具人才的培养目标出发,设计出了本副可换镶件多功能教学注射模,包含了两板注射模的经典结构、材料、CNC加工的全流程工序,巧妙的加入了实用性和趣味性的产品结构设计,体现和涵盖了注射模的核心结构,通过本副模具的设计和推广,为企业和职业院校模具制造与设计专业学生提供专业实训教具参考和学习。

喷水螺杆压缩机在瓦斯压缩中的应用研究

活塞式压缩机压缩瓦斯气过程中,会造成瓦斯气温度升高,导致瓦斯的爆炸上限超过瓦斯中的甲烷浓度,一旦遇到火源就可能发生瓦斯爆炸。喷水螺杆压缩机对瓦斯气进行压缩的过程中,不断地向瓦斯气进行喷水冷却,利用水带走瓦斯气压缩产生的热量,可确保瓦斯气浓度在整个压缩过程中都处于爆炸极限范围之外,保证了瓦斯气压缩过程的安全性。介绍了喷水螺杆压缩机在贵州盘江瓦斯气制LNG项目的应用实践,结果表明其作为瓦斯气压缩机,解决了活塞式压缩机排气温度过高和泄漏量大的问题,可作为瓦斯气制CNG/LNG工艺的首选机型。

注射用益气复脉(冻干)对力竭游泳大鼠的抗疲劳作用研究

目的:通过大鼠力竭游泳模型考察注射用益气复脉(冻干)(YQFM)的抗疲劳作用。方法:50只Sprague-Dawley(SD)大鼠随机分成对照组、模型组、YQFM低、中、高(231.5、463和926 mg/kg)剂量组,每组10只。检测各组大鼠游泳时间、血清中葡萄糖、乳酸和尿素氮(BUN)及谷胱甘肽过氧化物酶(Gsh-Px)、丙二醛(MDA)、超氧化物歧化酶(SOD)和组织中的肝糖原、肌糖原含量。结果:力竭游泳后大鼠表现出一定的倦态和反应迟钝等现象,YQFM组症状不明显;与模型组相比,YQFM各剂量组大鼠的游泳时间均提高(均P<0.001);与模型组相比,YQFM组葡萄糖、Gsh-Px和MDA、SOD含量和组织中肝糖原、肌糖原水平显著升高(均P<0.001),乳酸、BUN水平显著降低(均P<0.001),均呈剂量依赖性。结论:YQFM可以显著改善力竭游泳大鼠的疲劳症状,补充其体内葡萄糖,减少乳酸堆积和糖原分解,并提高抗氧化活性物质等生化指标水平,对运动性疲劳具有一定的改善作用。

Inhibition Effect of Water Injection on Afterburning of Rocket Motor Exhaust Plume

One of the most important characteristic signatures of the exhaust plume from rocket motor is the aflerbuming phenomenon, and the injected water into the plume could inhibit the afterburning. The calculation model for the gas-liquid multiphase flow field with chemical reaction in the plume is built. By inducing the energy source terms caused by the vaporization of liquid water, condensation of the vapor and chemical reaction in the energy equation, the gas-liquid multiphase flow field and the afterburning phenomenon are calculated in a coupling way. Mixture multiphase flow model is used to calculate the gas-liquid flow field, and the vaporization mechanism is used to investigate the water vaporization process. The temperature contours are obtained and accord well with the experimental photos. The mass fraction contours of primary species are obtained, which can indicate the extent of inhibition effect of water injection on the afterburning phenomenon in the plume. When water is injected into the plume, the region of aflerburning reduces a lot, and temperature on the ground wall declines rapidly, which can decrease the ablation of the combustion gas to the launch ground.

注入式低温等离子体用于某卷烟厂异味处理研究

为了更好地发挥注入式低温等离子体在烟草废气处理中的优势,将其用于某卷烟厂新建的膨胀烟丝工房车间,采用除尘排潮系统处理,将二级高效能交叉流化学洗池设备(水洗技术)与注入式低温等离子设备相结合,风量60000 m^(3)/h,异味处理效率达到了90%,臭气排放浓度小于500无量纲,达到了国家排放标准。

Experimental Investigation for NO_x Emission Reduction in Hydrogen Fueled Spark Ignition Engine Using Spark Timing Retardation, Exhaust Gas Recirculation and Water Injection Techniques

The experimental tests were carried out on a single cylinder hydrogen fueled spark ignition(SI)generator set with different spark timings(4-20℃A bTDC),exhaust gas recirculation(EGR)up to 28% by volume and water injection up to 1.95 kg/h(maximum water to fuel mass ratio of 8:1).The engine speed was kept constant of 3000 r/min.The NOx emission and thermal efficiency of engine with gasoline and hydrogen fuel operation at 1.4 kW power output are 5 g/kWh and 12.1 g/kWh,and 15% and 20.9% respectively.In order to reduce the NOx emission at source level,retarding spark timing,exhaust gas recirculation(EGR),and water injection techniques were studied.Nox emission decreased with spark timing retardation,EGR,and water injection.NOx emission with hydrogen at 1.4 kW power output decreased from 12.1 g/kWh with maximum brake torque(MBT)spark timing(10℃A bTDC)to 8.1 g/kWh with retarded spark timing(4℃A bTDC)due to decrease in the in-cylinder peak pressure and temperature.The Nox emission decreased to 6.1 g/kWh with 20% EGR due to thermal and chemical dilution effect.However,thermal efficiency decreased about 33% and 17% with spark timing retardation and 20EGR respectively as compared to that of MBT spark timing.But,in the case of water injection,the NOx emission decreased significantly without affecting the thermal efficiency of the engine and it is 5.6 g/kWh with water-hydrogen ratio of 4:1(water flow rate of 0.92 kg/h).Water injection is the best suitable method to reduce the NOx emission in a hydrogen fueled engine compared with the spark timing retardation and EGR technique.

Numerical study of effect of post injection coupled with EGR on combustion and emission performances of CRDI engine fueled with biodiesel-ethanol blends

Energy shortage and environmental pollution are becoming more serious,biodiesel is regarded as the most promising alternative fuel for diesel engines due to its environmentally friendly and renewable characteristics.In this study,the biodiesel-ethanol blends were used in a diesel engine,and the purpose of the study was to simultaneously control the NOx and soot emissions of the diesel engine by adjusting the injection strategy and EGR rate.A turbocharged,six-cylinder,common rail direct injection(CRDI)engine model was established using GT-Power.The effects of the main-post injection strategy and post injection coupled with exhaust gas recirculation(EGR)on combustion and emission characteristics were investigated at a maximum torque speed and a medium load.The results show that when the main-post injection strategy is employed,the combustion duration of the main injection is shortened with an increase in the main-post injection interval(MPI).When the MPI increased to more than 18℃A,the heat release of post injection could be observed clearly from the curve of the heat release rate,NOx emissions decreased by 5.70%and 7.12%,respectively,and soot emissions decreased by 25.56%and 30.20%,respectively.Moreover,with the increasing post injection quantity,the combustion duration of the main injection shortened,and the peak heat release rate(PHRR)of the post injection increased.When the fuel quantity for the post injection increased from 2 to 6 mg,NOx emissions decreased from 2.33%to 9.80%,and soot emissions decreased from 16.10%to 34.97%.The effect of post injection quantity on emissions was more significant than that of the MPI.In addition,with increasing EGR rate,the ignition delay is prolonged,the peak cylinder pressure,PHRR,peak combustion temperature and NOx emissions decrease,whereas soot emissions increase gradually.Main-post injection can improve the NO-soot trade-off,the optimal EGR rate is 22.86%under a post injection quantity of 4 mg and a MPI of 22℃A.

缸内远后喷与排气管喷油在DPF主动再生过程中的性能对比研究

在一台高压共轨柴油机上,进行了缸内远后喷与排气管喷油在DPF主动再生过程中的性能对比研究。试验结果表明,相同再生热管理水平下,缸内远后喷再生持续时间长,再生油耗及HC泄露偏高。经过再生限油后,缸内远后喷再生过程HC泄露峰值降低约55%,但仍然比排气管喷油再生偏高。研究结果为DPF再生方法及其控制策略的制定及优化提供理论依据。

原油含水率增加对海上油田注汽锅炉运行的影响

受原油含水率增加的影响,海上油田注汽锅炉经常出现排烟温度升高、燃烧器结焦和换热管路腐蚀加剧等问题。为了保障海上油田注汽锅炉的运行性能,本文对锅炉积灰物和原油含水率进行了化验分析,本文以详细的计算和运行数据为依据,揭示了原油含水率升高对锅炉运行性能的影响规律。研究发现原油含水率增大后,Na^(+)离子和Cl^(-)离子含量增多。盐分在换热管路上凝结后,加速了换热管道的腐蚀过程,并降低了换热管道的换热效率,进一步引起注汽锅炉排烟温度升高。当原油含水率增加至10%时,其低位发热量降低了9.7%,粘度增加了1.39倍,注汽锅炉排烟热损失增加了16.9%。