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无氢渗碳 2

双层辉光离子渗金属 1

喷钠 1

多目标粒子群协同优化算法 1

抗磨 1

时效硬化高速钢 1

核燃料循环 1

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烧氘型核装置 1

烧结终点 1

爆洞 1

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Sequential degradation-based burn-in test with multiple periodic inspections

《工程管理前沿（英文）》 2021年第8卷第4期页码 519-530 doi: 10.1007/s42524-021-0166-0

摘要： Burn-in has been proven effective in identifying and removing defective products before they are delivered to customers. Most existing burn-in models adopt a one-shot scheme, which may not be sufficient enough for identification. Borrowing the idea from sequential inspections for remaining useful life prediction and accelerated lifetime test, this study proposes a sequential degradation-based burn-in model with multiple periodic inspections. At each inspection epoch, the posterior probability that a product belongs to a normal one is updated with the inspected degradation level. Based on the degradation level and the updated posterior probability, a product can be disposed, put into field use, or kept in the test till the next inspection epoch. We cast the problem into a partially observed Markov decision process to minimize the expected total burn-in cost of a product, and derive some interesting structures of the optimal policy. Then, algorithms are provided to find the joint optimal inspection period and number of inspections in steps. A numerical study is also provided to illustrate the effectiveness of our proposed model.

关键词： burn-in degradation multiple inspections Wiener process partially observed Markov decision process

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Monocyte subsets and their differentiation tendency after burn injury

null

《医学前沿（英文）》 2013年第7卷第4期页码 397-400 doi: 10.1007/s11684-013-0298-7

摘要：

Monocytes are critical effectors and regulators of immune response. Studying the nomenclature of monocyte subsets may be beneficial for understanding the complex function of monocytes in steady and inflammatory states. A monocyte has the potential to differentiate into dendritic cells or macrophages, and this behavior significantly changes in severely burned patients and mice. The findings in the present study may help enhance understanding on the perturbation of the immune system after severe burn injury.

关键词： monocyte differentiation burn

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Achievements in burn surgery over the past 50 years in China

WANG Shiliang

《医学前沿（英文）》 2008年第2卷第4期页码 332-336 doi: 10.1007/s11684-008-0063-5

摘要： This paper reflects on the advancements of clinical and scientific research in the field of burn surgery in China. It includes emergency care of massive burns, resuscitation, anti-infection, prevention and cure of internal organ injuries, metabolic and nutritional support, wound repair and rehabilitation, and special types of burns; it also covers pathology, microbiology, immunology, cell biology, molecular biology, and tissue engineering.

关键词： immunology scientific nutritional microbiology engineering

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Numerical simulation of charge stratifications to improve combustion and NO formation of lean-burn SI

Zhijun PENG ,

《能源前沿（英文）》 2009年第3卷第3期页码 353-358 doi: 10.1007/s11708-009-0035-8

摘要： The influences of charge stratification on spark ignition (SI) engine combustion and NO emission were analyzed using a phenomenological model. The mixture in the cylinder was divided spherically into three parts: a central core with a stoichiometric air-fuel charge, a dilution region without any combustible charge, and a mixing region lying between the core and the dilution region. Three mixture stratification parameters such as the extent of dilution in the mixing region, the extent of combustible charge in the mixing region, and the gradient of stratification in the mixing region were investigated. The results indicate that the extent of combustible charge in the mixing region could reduce in-cylinder NO formation significantly, compared with the extent of dilution in the mixing region. As long as the degree of dilution in the mixing region is within the dilution limit of the combustible charge, the gradient of dilution has little effect on combustion and NO formation.

关键词： charge stratification SI engine lean-burn combustion NO emission

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Experimental study of stratified lean burn characteristics on a dual injection gasoline engine

Chun XIA, Tingyu ZHAO, Junhua FANG, Lei ZHU, Zhen HUANG

《能源前沿（英文）》 2022年第16卷第6期页码 900-915 doi: 10.1007/s11708-021-0812-6

摘要： Due to increasingly stringent fuel consumption and emission regulation, improving thermal efficiency and reducing particulate matter emissions are two main issues for next generation gasoline engine. Lean burn mode could greatly reduce pumping loss and decrease the fuel consumption of gasoline engines, although the burning rate is decreased by higher diluted intake air. In this study, dual injection stratified combustion mode is used to accelerate the burning rate of lean burn by increasing the fuel concentration near the spark plug. The effects of engine control parameters such as the excess air coefficient (Lambda), direct injection (DI) ratio, spark interval with DI, and DI timing on combustion, fuel consumption, gaseous emissions, and particulate emissions of a dual injection gasoline engine are studied. It is shown that the lean burn limit can be extended to Lambda= 1.8 with a low compression ratio of 10, while the fuel consumption can be obviously improved at Lambda= 1.4. There exists a spark window for dual injection stratified lean burn mode, in which the spark timing has a weak effect on combustion. With optimization of the control parameters, the brake specific fuel consumption (BSFC) decreases 9.05% more than that of original stoichiometric combustion with DI as 2 bar brake mean effective pressure (BMEP) at a 2000 r/min engine speed. The NO_x emissions before three-way catalyst (TWC) are 71.31% lower than that of the original engine while the particle number (PN) is 81.45% lower than the original engine. The dual injection stratified lean burn has a wide range of applications which can effectively reduce fuel consumption and particulate emissions. The BSFC reduction rate is higher than 5% and the PN reduction rate is more than 50% with the speed lower than 2400 r/min and the load lower than 5 bar.

关键词： dual injection stratified lean burn gasoline engine particulate matter emission combustion analysis

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Progress in developing an innovative lean burn catalytic turbine technology for fugitive methane mitigation

Shi SU, Xinxiang YU

《能源前沿（英文）》 2011年第5卷第2期页码 229-235 doi: 10.1007/s11708-011-0147-9

摘要： Approximately 2.8 × 10 m of methane is emitted per year to the atmosphere from coal mining activities around the world. Mitigation and utilization of the fugitive coal mine methane is very difficult because its concentration is very low and varies from 0.1% to1%, and the methane is contained in a large air flow rate of 150–400 m /s. This paper overviews existing and developing technologies for the mitigation and utilization of the fugitive mine methane, and then presents research progress in developing an innovative lean burn catalytic turbine technology for fugitive methane mitigation and utilization. This turbine system can be powered with about 1% methane in air.

关键词： coal mine methane mitigation and utilization lean burn gas turbine catalytic combustion

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Selective catalytic reduction of NOx from exhaust of lean-burn engine over Ag-Al2O3/cordierite catalyst

LI Junhua, KANG Shoufang, FU Lixin, HAO Jiming

《环境科学与工程前沿（英文）》 2007年第1卷第2期页码 143-146 doi: 10.1007/s11783-007-0025-1

摘要： A highly effective Ag-AlO catalyst was prepared using the sol-gel method, and characterized by surface area using nitrogen adsorption, scanning electron microscopy (SEM), and transmission electron microscopy (TEM) techniques. The catalyst performance was tested on a real lean-burn gasoline engine. Only unburned hydrocarbons and carbon monoxide in the exhaust were directly used as reductant (without any external reductant), the maximum NO conversion could only reach 40% at 450?C. When an external reductant, ethanol was added, the average NO conversion was greater than 60%. At exhaust gas temperature range of 350 500?C, the maximum NO conversion reached about 90%. CO and HC could be efficiently oxidized with Pt-AO oxidation catalyst placed at the end of SCR converter. However, NO conversion drastically decreased because of the oxidation of some intermediates to NO again. The possible reaction mechanism was proposed as two typical processes, nitration, and reduction in HC-SCR over Ag-AlO.

关键词： lean-burn gasoline external reductant nitrogen adsorption conversion catalyst performance

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精准烧伤医学：分子工程科学应用

Kristen Jakubowski, Michael Poellmann, Raphael C. Lee

《工程（英文）》 2015年第1卷第3期页码 280-281 doi: 10.15302/J-ENG-2015073

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钛合金离子渗镀表面处理新进展

张高会,徐　重,张平则,葛洪良,崔玉建,温廷敦,潘俊德

《中国工程科学》 2007年第9卷第11期页码 163-166

摘要：

介绍了钛合金表面加弧辉光离子无氢渗镀碳、双层辉光离子无氢渗碳、双层辉光离子渗铬、渗铜等表面处理的新方法；检测结果显示在钛合金表面均形成了梯度合金层，进一步检测表明，表面渗镀合金层对改善钛合金耐磨、耐蚀和阻燃性均有显著的作用。

关键词：钛合金无氢渗碳抗磨阻燃

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基于多目标粒子群协同算法的状态参数优化

丁雷,吴敏,佘锦华,段平

《中国工程科学》 2010年第12卷第2期页码 101-107

摘要：

针对铅锌烧结过程综合透气性、烧结终点的优化具有强非线性、计算复杂等特点，提出了一种有效的多目标粒子群协同优化算法。首先，建立了有综合透气性、烧结终点两个目标的优化模型。接着，通过改进的约束比较方法、粒子极值选取方法，以及利用不同的粒子群来分别优化相应的变量，提出了一种改进的多目标粒子群协同优化算法。最后，利用提出的多目标优化算法进行综合透气性、烧结终点的优化。仿真结果表明，所提出的多目标优化算法能较好地解决综合透气性、烧结终点的优化问题。

关键词：铅锌烧结过程综合透气性烧结终点多目标粒子群协同优化算法