柴油机燃用LPG的高原特性实验研究

在高原环境条件下 ,针对柴油机燃用LPG的经济性、动力性和排放特性进行了研究。柴油机掺烧LPG后 ,在一定的掺烧比下 ,动力性有所提高 ,经济性有所改善 ,碳烟排放降低幅度较大 ,但发动机振动加大 ,噪声和排温升高。

离心压气机高原特性数值计算与分析

针对高原环境下工作的车用柴油机涡轮增压器,对压气机不同进口条件的影响进行了理论分析.根据流体物性对数值计算的影响提出了高原压气机的数值计算方法.通过数值仿真结果及其内部流场的对比分析,讨论了高原条件下压气机特性影响的关键因素和变化规律.结果表明:高原条件下等转速的压气机效率下降,压比上升.叶片前缘的激波损失和间隙流损失的加剧是高原条件下压气机效率下降的主要原因.

电梯驱动主机高原特性试验加载装置设计及应用

为了探究电梯在高原环境下的运行特性,本文以电梯驱动主机为主要试验对象,分析了高原环境对其性能的潜在影响,设计了有限空间范围内的驱动主机加载试验装置,实现了在实验室内对电梯驱动主机的高原特性试验,并对其制动器线圈和电机定子绕组温升特性进行了对比试验,验证了装置的有效性,初步探究了电梯驱动主机高原特性的相关规律。

RPA对PFI轻型汽油车RDE高原排放特性试验研究

为探讨RPA对PFI汽油车在RDE试验中排放特性影响,采用了AVL-M. O. V. E.轻型车便携式排放测试系统PEMS对某电控进气道多点喷射汽油车分别在西宁高海拔地区进行了平缓、一般和激烈3种驾驶行为下的RDE排放试验研究,试验中未对发动机进行任何改动。结果表明:国标对RDE试验要求的RPA值范围较大,不同RPA值对应的驾驶行为直接影响RDE排放试验结果。RDE冷起动阶段对PN和CO排放的影响较大,且对PN排放的影响大于对气体污染物排放的影响。CO和PN排放随RPA值的变化无明显变化规律; NOx和CO2排放量与RPA值呈现正相关。CF(NOx)> CF(CO)> CF(PN),且CF(NOx)随着RPA值的增加,变化幅度明显增大,高原条件下进行RDE试验,需要注意NOx排放。RPA值影响CO2排放在特性曲线图上的分布,RPA值越大,CO2排放在特性曲线图上的分布越靠近上公差。

轻型汽油车实际行驶污染物高原排放特性试验研究

为研究PFI轻型汽油车高原条件下的实际行驶污染物排放(RDE)特性,对某电控进气道多点喷射汽油车分别在平原和高原地区进行了实际行驶污染物排放试验研究。试验时未对发动机进行任何改动。结果表明:冷起动阶段各污染物排放结果明显较高。比较平原工况,RDE冷起动阶段高原工况下的CO、NOX和PN排放量分别升高90.03%、742.45%和93.90%。平原工况下的CO排放量在城郊工况时最多,城区工况时最少;NOX排放量在各工况下差异不大;PN排放量在城郊工况最多,高速工况时最少。高原工况下的CO排放量在高速工况时最多,城区工况时最少;NOX和PN排放量在城区工况时最多,城郊工况时最少。RDE试验工况下,平原工况时的PN排放量在城区、城郊、高速和综合工况下分别约为高原工况时PN真实排放量的2.3倍、11.9倍、4.7倍和4.3倍。

非道路涡轮增压柴油机高原适应性研究

为改善非道路柴油机高海拔条件下功率下降、经济性及排放性能恶化、高速增压器超速等问题,利用柴油机高原环境模拟台架试验结合一维仿真研究了0~4000 m海拔环境下增压器运行特性、柴油机综合性能参数等随海拔高度的变化规律及影响机理。针对柴油机的变海拔性能恢复目标,通过对增压系统进行参数计算和选配,提出一种带有废气旁通阀的两级涡轮增压匹配方案。研究结果表明:变海拔条件下,非道路柴油机各性能参数呈现非线性变化,在转速800~2800 r/min全负荷工况下,柴油机动力性、经济性变化梯度呈现出先减小后增大的“浴盆形”趋势。在0~2000 m海拔环境下,柴油机转矩降幅达4.3%,有效燃油消耗率降幅达6%。随着海拔升高,中冷前温度与涡前温度逐渐升高,增压压力与涡前压力逐渐降低,CO、全碳氢和NOx排放升高。匹配两级增压系统后,对比原机4000 m海拔运行工况,柴油机功率平均升高14.9%,有效燃油消耗率平均降低11.8%,实现了非道路柴油机的高海拔性能恢复目标。

模拟高原条件下含氧燃料对发动机性能的影响

以掺混不同体积分数（5%、10%）二乙二醇二甲醚（DGM）的柴油为燃料,采用F6L913柴油机进行发动机台架试验,通过控制进气压力模拟高原地区柴油机的工作条件,考察了海拔2000-4000m下不同掺混比例的含氧燃料对发动机性能的影响。结果表明,在海拔2000m以上地区,发动机燃用含氧燃料的功率均大于燃用纯柴油,且功率会随燃料中DGM添加量的增加而增大;海拔越高,转速越大,燃用含氧燃料时发动机动力性越好。在海拔2000m以上地区,发动机燃用含氧燃料的燃油消耗率比燃用纯柴油低,且会随着海拔的升高和DGM添加量的增加而明显降低;含氧燃料可以显著降低柴油机高原地区碳烟、HC、CO的排放,NOx排放有所增加。在高原地区使用高含氧燃料是恢复柴油机性能的有效方法。

高原环境下汽油机微粒捕集器(GPF)过滤效率的研究进展

基于国家第六阶段机动车污染物排放标准的要求以及中国高原区域广阔和高原环境下机动车排放与型式认证工况排放差别较大,且国内外对高原环境下GPF的捕集特性、效率研究甚少。因此,阐述了高原环境对汽油机尾气排放颗粒的影响因素、高原环境下汽油机尾气排放特性和GPF捕集效率的影响因素,并对高原环境GPF的工作特性和过滤效率后期研究进行展望。

蕨麻小型猪的血液生理生化指标初探

目的 比较不同海拔地区饲养的蕨麻小型猪血液生理生化指标差异,为蕨麻小型猪的实验动物化提供基础数据.方法 高原地区（甘南,3 200 m）蕨麻小型猪（1组）采集血样后,将该群小型猪移至中度高原地区（兰州,1 500 m）饲养,分别于饲养3个月（2组）和6个月（3组）时采集血样,测定和比较10项血液生理指标和32项血液生化指标.结果 2组性别间部分血液生理生化指标存在差异（P＜0.05或P＜0.01）,1组、3组性别间无差异.1组与2、3组比较,雌性血液生理指标中红细胞计数（RBC）等8项有明显变化（P＜0.05或P＜0.01）,生化指标乳酸脱氢酶（LDH）、丙氨酸转氨酶（ALT）有差异（P＜0.05或P＜0.01）.雄性血液生理指标白细胞计数（WBC）等7项有明显变化（P＜0.05或P＜0.01）,生化指标较多有明显变化（P＜0.05或P＜0.01）.结论 蕨麻小型猪由高原引至中度高原地区饲养,部分血液生理生化指标受到生长环境、气候条件、营养水平、养殖方式的影响,但大多仍然具有高原特性,适合作为高原病研究的实验动物,在中度高原地区对蕨麻小型猪进行实验动物化培育具有可行性.

论青海高速公路绿化对环境保护作用

详细阐述了高等级公路绿化的必要性,充分论证了青海省高速公路绿化对周边环境的保护作用及在水土流失方面起到的积极作用,根据青海省内的自然条件,比较详细的罗列出了青海高等级公路的绿化特点与难点,针对难点一一找出了切实可行的改善方法与手段。

Research on Crustal Flow and Its Dynamic Characteristics in Sichuan and Its Adjacent Area

Using the broadband seismic data of the regional stations in the Sichuan Digital Seismic Network and the mobile seismic stations in this region,the receiver function inversion method was adopted to study the characteristics of crustal flow and dynamic effects in Sichuan and adjacent areas. The results show that: Velocity in the crust and upper mantle of the Sichuan basin is significantly higher than that beneath the eastern margin of the Qinghai-Tibetan plateau. The velocity v_S is from 3. 6 to 3. 8km / s in the crust and4. 5- 4. 8km / s in the upper mantle beneath the basin,and there is no low-velocity layer in the crust. The lithology shows a hard block. The v_S velocity in the eastern margin of the Qinghai-Tibetan plateau is lower,with average v_Sof 3. 0- 3. 4km / s in the mid crust and4. 0- 4. 5km / s in the upper mantle. Low-velocity layers are distributed widely in the crust,most of which are in the mid crust at a depth of 20km- 40 km,and there are also a few low-velocity layers appearing in the upper crust at depths of 10km- 20 km and the lower crust at depths of 40km- 60 km. Affected by the northward pushing of the Indian plate,the eastward movement of the eastern margin of the Qinghai-Tibetan plateau is blocked by the hard Sichuan basin,producing a southward and southeastward component.Such movement process is produced by the complicated forces acting in this area. Just under the action of these forces, the eastern margin of the Qinghai-Tibetan plateau becomes a region with complicated geology and intensive earthquake activity. Obstructed by the hard Sichuan basin,the low-velocity crustal flow is delaminated and split into two or three upward and downward tributaries. The upward flow intruded into the upper crust,causing uplift of the earths urface,forming mountain crests; the downward flow intruded into the lower crust and upper mantle,resulting in thickening of the crust and depression of the Moho. The crustal flow in the eastern margin of the Qinghai-Tibetan plateau is mainly distributed along the active faults. The crustal flow flows out from the Qiangtang block in the middle part of the eastern margin of the Qinghai-Tibetan plateau,the mainstream flows along the NW-SE trending Xianshuihe fault zone,then turns NS and flows to the south along the Anninghe and Xiaojiang faults. There is another crustal flow in the north of the study area,flowing in the NE and E-W directions to the Longmenshan faults.

Evaluation of a water-soluble adjuvant for the development of monoclonal antibodies against small-molecule compounds

A water-soluble adjuvant named QuickAntibody （QA） was introduced into the procedure of mouse immunization for the development of hapten-specific monoclonal antibodies （mAbs）, using four kinds of pesticides as model compounds. Compared with conventional Freund＇s adjuvants, QA treatments offered relatively low but acceptable antiserum titers after three inoculations, gave little adverse effects to the experimental animals, and were preferable in harvesting splenocytes during the steps of cell fusion. Afterwards, hybridomas from the QA group were prepared and screened by both non-competitive and competitive indirect enzyme-linked immunosorbent assays （ELISAs）. The efficiency of gaining immune-positive hybridomas was satisfactory, and the resultant mAbs showed sensitivities （half maximal inhibitory concentration （IC50）） of 0.91, 2.46, 3.72, and 6.22 ng/ml to triazophos, parathion, chlorpyrifos, and fenpropathrin, respectively. Additionally, the performance of QA adjuvant was further confirmed by acquiring a high-affinity mAb against okadaic acid （IC50 of 0.36 ng/ml） after three immunizations. These newly developed mAbs showed similar or even better sensitivities compared with previously reported mAbs specific to the corresponding analytes. This study suggested that the easy-to-use adjuvant could be applicable to the efficient gen- eration of highly sensitive mAbs against small compounds.

Modeling permafrost properties in the Qinghai-Xizang(Tibet) Plateau

Water and heat dynamics in the active layer at a monitoring site in the Tanggula Mountains, located in the permafrost region of the Qinghai-Xizang （Tibet） Plateau （QXP）, were studied using the physical-process-based COUPMODEL model, including the interaction between soil temperature and moisture under freeze-thaw cycles. Meteorological, ground temperature and moisture data from different depths within the active layer were used to calibrate and validate the model. The results indicate that the calibrated model satisfactorily simulates the soil temperatures from the top to the bottom of the soil layers as well as the moisture content of the active layer in permafrost regions. The simulated soil heat flux at depths of 0 to 20 cm was consistent with the monitoring data, and the simulations of the radiation balance components were reasonable. Energy consumed for phase change was estimated from the simulated ice content during the freeze/thaw processes from 2007 to 2008. Using this model, the active layer thickness and the energy consumed for phase change were predicted for future climate warming scenarioS. The model predicts an increase of the active layer thickness from the current 330 cm to approximately 350-390 cm as a result of a 1-2℃ warming. However, the effect active layer thickness of more precipitation is limited when the precipitation is increased by 20%-50%. The COUPMODEL provides a useful tool for predicting and understanding the fate of permafrost in the QXP under a warming climate.

Magnetic characteristics of insoluble microparticles in ice core (Nojingkangsang) from the southern Tibetan Plateau and its environmental significance

Insoluble microparticles in ice cores are related closely to the transportation of eolian dust,and thus are important natural media to reconstruct climate change.In this study,we conducted a systematic mineral-magnetic investigation of insoluble microparticles in the Nojingkangsang ice core (29°2.1'N,90°11.88'E,5950 m) from the Southern Tibetan Plateau.Results indicate that the dominant magnetic mineral is magnetite,and its concentration has grown significantly since the 1980s,which coincides with trends in climate warming of the Tibetan Plateau.Influenced by regional warming,the glacial recession around Nojingkangsang shortens the distance between the dust source and glacial areas and thus increases the concentration of coarse-grained magnetic minerals in ice cores.However,the frequency of dust storms,associated with annual precipitation,could play only a regulatory role on the magnetic content over yearly (or seasonal) time scales.Therefore,using a new approach,the magnetic index of insoluble microparticles in ice cores of this region is seen as mainly reflecting trends in climate warming.

Thermodynamics properties and thermal conductivity of Mg_2Pb at high pressure

The thermodynamics properties and thermal conductivity of Mg2Pb at high pressures have been calculated by first-principles.The enthalpy of formation and heat capacity obtained at 0 GPa are in good agreement with the experiments and other theoretical results.The thermal conductivity and coefficient of thermal expansion of Mg2 Pb at high pressure were evaluated.The thermal conductivity presents a second-order polynomial with pressure.The calculated thermal conductivity of Mg2Pb indicates that it is suitable to be used as thermal conductor at 0 K.