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Improving the performance of LOX/kerosene upper stage rocket engines

Propulsion and Power Research 2017年第3期6卷 157-176页

作者： Igor N.Nikischenko raymond d.wright Roman A.Marchan Firefly Europe B.V. Blaricum 1261 GAThe Netherlands Spacefleet Ltd DevizesWiltshireSN103APUnited Kingdom

Improved liquid rocket engine cycles were proposed and analyzed via comparison with existing staged combustion and gas-generator *** key features of the proposed cycles are regenerative cooling of thrust chamber by oxygen and subsequent use of this oxygen for driving one or two oxygen *** fuel pump(s)are driven in a conventional manner,for example,using a fuel-rich gas-generator *** with staged combustion cycle based on oxygen-rich pre-burner showed that one of the proposed semi-expander cycles has a specific impulse only on 0.4%lower while providing much lower oxygen temperature,more efficient tank pressurizing system and built-in roll *** semi-expander cycle can be considered as a more reliable and cost-effective alternative of staged combustion *** semi-expander cycle can be considered as an improvement of gas-generator *** proposed semi-expander cycles were developed as a derivative of thrust chamber regenerative cooling performed by *** of existing oxygen/kerosene engines showed that replacing of kerosene regenerative cooling with oxygen allows a significant increase of achievable specific impulse,via optimization of mixture *** is especially the case for upper stage *** increasing of propellants average density can be considered as an additional benefit of mixture ratio *** was demonstrated that oxygen regenerative cooling of thrust chamber is a feasible and the most promising option for oxygen/kerosene *** of oxygen regenerative cooling and semi-expander cycles potentially allows creating the oxygen/kerosene propulsion systems with minimum specific impulse *** is important that such propulsion systems can be fully based on inherited and well-proven technical solutions.A hypothetic upper stage engine with thrust 19.6 kN was chosen as a prospective candidate for theoretical analysis of the proposed semi-expander *** newly-developed software RECS

关键词： Oxygen Kerosene Liquid rocket engine Upper stage

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Analysis of switching conditions of chalcogenide alloys during crystallization

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Journal of University of Science and Technology Beijing 2006年第5期13卷 446-449页

作者： Wanhua Yu C.d. wright Materials Science and Engineering School University of Science and Technology Beijing Beijing 100083 China School of Engineering and Computer Science University of Exeter Exeter EX4 4QF UK

To understand the principle and limitation of chalcogenide alloy Ge2Sb2Te5 （GST） in solid-state memory devices during crystallization, it was necessary to develop a physically realistic model that could reflect the electrical and thermal properties of these media. A novel comprehensive numerical model has been developed for simulating these memory devices, which describes the electrical and thermal behavior using the solution of the nonlinear, time-dependent electrical and heat conduction equation. The finite-difference-time-domain technique was adopted to compute the electrical field and heat distribution in the device. Several contributing factors that affect the crystallization switching process such as the geometry of the GST layer, temperature and electric field dependency of the electrical conductivity have been discussed. The results of the simulations were then used to provide critical guidelines for fabrication and optimization of the device performance.

关键词： chalcogenide alloy crystallization simulation modeling memory

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高油酸玉米突变体的诱导和遗传分析

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作物学报 1998年第4期24卷 447-451页

作者：刘治先 Allen d.wright Ming T.Chang 山东省农业科学院玉米研究所山东济南250100 美国依阿华州立大学艾姆斯ia50011

油酸、亚油酸及饱和脂肪酸含量决定玉米油的品质。研究结果表明,利用EMS花粉诱变技术,可获得高油酸等玉米突变体。高油酸含量的遗传受部分显性主效基因控制;基因的显性方向指向增效。但是,在同一基因位点上,可能受一些微效复等位基因累... 详细信息

油酸、亚油酸及饱和脂肪酸含量决定玉米油的品质。研究结果表明,利用EMS花粉诱变技术,可获得高油酸等玉米突变体。高油酸含量的遗传受部分显性主效基因控制;基因的显性方向指向增效。但是,在同一基因位点上,可能受一些微效复等位基因累加作用的影响。卡平方检验符合1对部分显性基因的遗传规律。与同类研究结果基本一致。优质油玉米育种,不仅要提高玉米的含油量,还应提高油分中的油酸含量,降低饱和脂肪酸含量,改善玉米油的品质。

关键词：玉米油油酸含量突变体遗传分析优质油玉米育种

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反垄断与反不正当竞争的关系

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竞争政策研究 2016年第3期 5-8页

作者： Joshua d.wright 美国乔治梅森大学法学院

反垄断与反不正当竞争的关系是全球所有既涉及反垄断执法又涉及反不正当竞争执法的执法机构所普遍关注的问题。通过简要分析美国反垄断分析的基本框架和原则,明确这一框架之下"不正当竞争"的含义,同时结合美国联邦贸易委员会(FTC)

关键词：不正当竞争反垄断执法反不正当竞争法美国反垄断法消费者福利联邦贸易委员会反垄断法规先市场市场竞争者静态效率

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影响冻干卡介苗稳定性的因素

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生物制品参考资料 1973年 87-90页

作者： d.wright 王秉瑞

Shackell(1909)发现微生物可用冻干法保存。冻干方法在早期抗菌素的干燥中曾有相当的进展,并应用于卡介苗的冻干。Leschinskaya(1944)首先报告及此。Frobisher等(1949)指出分枝杆菌可保存17年之久(1931—1948)。之后,许多工作者都指出... 详细信息

Shackell(1909)发现微生物可用冻干法保存。冻干方法在早期抗菌素的干燥中曾有相当的进展,并应用于卡介苗的冻干。Leschinskaya(1944)首先报告及此。Frobisher等(1949)指出分枝杆菌可保存17年之久(1931—1948)。之后,许多工作者都指出下列因素对卡介苗稳定性的重要:

关键词：冻干卡介苗苏通培养基干燥保护剂

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裴欧沃夫

裴欧沃夫

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1959年

作者：（英）乌莱特（d.wright）陈国桦译

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Tunability of the mechanical properties of(Fe_(50)Mn_(27)Ni_(10)Cr_(13))_(100-x)Mo_(x) high-entropy alloys via secondary phase control

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Journal of Materials Science & Technology 2021年第14期73卷 210-217页

作者： raymond Kwesi Nutor Q.P.Cao X.d.Wang d.X.Zhang J.Z.Jiang International Center for New-Structured Materials(ICNSM) Laboratory of New-Structured MaterialsState Key Laboratory of Silicon Materialsand School of Materials Science and EngineeringZhejiang UniversityHangzhou 310027China State Key Laboratory of Modern Optical Instrumentation Zhejiang UniversityHangzhou 310027China

The single-phase face-centered cubic(fcc)-structured Fe_(50)Mn_(27)Ni_(10)Cr_(13) high entropy alloy(HEA)exhibits good ductility but low strength,which presents a *** Mo-alloying and thermomechanical treatments,we have designed the(Fe_(50)Mn_(27)Ni_(10)Cr_(13))_(100-x)Mo_(x)(x=0-6 at.%)alloy series with a wide range of mechanical *** careful control of secondary phases introduced in the cold-rolled and annealed(Fe_(50)Mn_(27)Ni_(10)Cr_(13))Mo_(2) sample resulted in an enhanced tensile strength from 250 MPa to 665 MPa,still having~25%*** investigations of this alloy revealed the presence of deformation twins,dislocation cells,and ordered bcc na no-pa rticles embedded in the ductile fcc matrix *** observed deformation structures are an indication of succes s ful cooperation between deformation twinning and precipitation strengthening in enhancing the tensile strength at maintained ductility compared to its cast *** work provides insight into the tunability of the mechanical properties of non-equiatomic HEAs via alloying and thermomechanical processing.

关键词： High-entropy alloys Mechanical property TEM

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Land use legacy for a tropical myco-heterotroph: how spatial patterns of abundance, reproductive effort and success vary

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Journal of Plant Ecology 2019年第2期12卷 367-375页

作者： Stephen McAuliffe James d.Ackerman raymond L.Tremblay department of Environmental Science Humboldt State UniversityArcataCAUSA Center for Applied Tropical Ecology and Conservation University of Puerto RicoSan JuanPRUSA department of Biology University of Puerto Rico17 Ave Universidad Suite 1701San JuanPR 00925-2537USA department of Biology University of Puerto RicoHumacaoPRUSA

Aims Human land use such as agriculture and logging can have cascad-ing effects on the environment and severely influence forest eco-systems by altering structure,species composition and community *** activities may have long-term consequences,which impact forest *** investigated the legacy of his-torical anthropogenic land use on the current reproductive effort(RE)and success of the understory,myco-heterotrophic orchid,Wullschlaegelia calcarata in Puerto Rico’s tropical rain forest after 80 years of forest *** Our study site was the 16-ha Luquillo Forest dynamics Plot in the Luquillo Experimental *** used six 10 m×500 m transect lines that spanned areas with differing levels of historic canopy coverage which are correlated with land use *** recorded the abundance of *** plants and measured shoot height,number of flowers,fruit set for all plants and seed set from the most mature,undehisced fruit on a random subset of plants *** sought to determine whether or not there is a legacy of land use history on the RE and success of *** the varying degrees of historic disturbance,we predicted that RE and success would be highest in minimally disturbed old-growth forest,and that soil type differences would be insufficient to affect RE or *** Findings We found 1607 plants of ***,and only one was detected in the most historically disturbed area of the *** orchids were most abundant in the two least historically disturbed ***,the prevailing trend in all measures of RE is in the opposite direction with greater RE in the forest plots with intermediate levels of histori-cal ***,the best model(as a function of AICc and weights)to predict RE is a combination of soil type and cover ***,our measures of reproductive success(fruit and seed set)were best in the least historically disturbed sites and were not associated with soil ***,the b

关键词： forest recovery Orchidaceae tropical forest disturbance ecology Wullschlaegelia

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Infrared spectroscopy analyses of air-CH_4 or air-CO gas flows interacting with polycrystalline CeO_2, La_2O_3 and Lu_2O_3 oxides

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Journal of Rare Earths 2012年第8期30卷 835-841页

作者： Bahcine BAKIZ Lamia BOURJA Abdeljalil BENLHACHEMI Frédéric GUINNETON Madjid ARAB Jean-raymond GAVARRI Institute Materials Microelectronics & Nanosciences of Provence UMR CNRS 6242 University SOUTH Toulon-Var Laboratory Materials & Environment Faculty of Sciences University Ibn Zohr

A comparative study of reactivity between air-CH4 or air-CO gas flows and CeO2, La2O3 and Lu2O3 rare earth oxides was per- formed using Fourier transform infrared spectroscopy analyses of CO2 gas resulted from the conversion of CH4 or CO gases. Polyerystalline samples of CeO2, La2O3 and Lu2O3 were first prepared by specific precipitation methods followed by low temperature calcination process. In the case of Lu2O3 oxide, a new specific route was proposed. Crystallite dimensions were determined by X-ray diffraction and transmission electron microscopy analyses. Morphologies were characterized using scanning electron microscopy. Specific surface areas were determined from Bnmauer-Emmett-Teller （BET） technique. Using infrared spectroscopy analyses, the conversion rates of CH4 or CO into CO2 were de- termined from the evolutions of CO2 vibrational band intensities, as a function of time and temperature. It was dearly established that, despite its low specific surface, the Lu2O3 oxide presented the highest capacity of conversion of CH4 or CO into CO2.

关键词： lutetium oxide rare earth oxides elaboration gas solid interactions infrared spectroscopy

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Plant-microbial fuel cell for electrical generation through living plants: an internal resistance insight into the plant species used

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Clean Energy 2024年第5期8卷 45-53页

作者： raymond daniel Rodriguez Martinez department of Industrial Production Faculty of EngineeringUniversidad Metropolitana1073 CaracasVenezuela

Climate change is a global threat,the presence of which has encouraged the development and implementation of renewable energies,including plant–microbial fuel cells,which could generate 6629568–33147840 MWh per year due to their large-scale *** of the main challenges associated with microbial cells is internal resistance—a parameter whose magnitude is influenced by sev-eral *** the case of plant–microbial fuel cells,adding a plant positively affects the mitigation of internal ***,the species employed is expected to play an important *** the present study,the objective was to determine as a general reference the internal resistance of cells using various plant species,among which were tomato(Solanum lycopersicum),black beans(Phaseolus vulgaris),aloe vera(Aloe vera),corn(Zea mays),and moss(dicranidae).For this purpose,an experimental procedure was carried out to compare the manual voltage measurements with a free cell concerning the voltage obtained by adding an external resistor in *** internal resistance values were determined as a function of the measured voltage,obtaining 177,179,175,324,and 233 kΩfor aloe vera,corn,tomato,black beans,and moss,*** this,it was shown that the roots of the plants represent an essen-tial addition to the internal resistance of the cell in the short *** contrast,plants with a C4 photosynthetic metabolism are more favourable,while C3 plants can also benefit from internal resistance during a more extended period of rhizodeposition.

关键词： climate change energy microorganism renewable source voltage

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