固体火箭发动机设计优化参数驾驭技术与应用研究——设计空间确定算法及快速优化方法

设计空间确定算法首先指定一个粗略设计空间,然后利用设计优化驾驭机制逐步调整设计变量值,使其进入满足系统约束的"绿色走廊",最终获得各设计变量取值范围,即为有效设计空间.基于试验设计和坐标轮换法的设计优化参数驾驭快速优化方法,首先通过试验设计对设计空间进行粗略探索,优选较好的设计初始点;从得到的初始点出发,应用坐标轮换思想进行设计优化,其中设计变量优选顺序和单变量优化方向,由设计人员运用设计优化参数驾驭手段,融合设计知识经验进行,最终获得一个或多个较优解.用于高压强固体火箭发动机的设计优化,设计空间确定算法使有效设计空间大大缩小,优化效率提高34%.快速优化方法使设计优化过程完全透明,可用于发动机初步方案设计阶段,快速获得多组较优设计方案.     

运载火箭及总体设计要求概论(三)——运载火箭总体设计(续)

简要介绍了运载火箭总体设计中气动力设计、气动热设计、弹道设计、载荷设计的主要内容、设计步骤和设计要点。     

基于Web的协同式PBN飞行程序设计模式的探索

引言基于Web的协同式设计方法适用于小组设计项目,这种设计模式可以通过Web服务器组织设计过程、显示设计进度、汇总设计成果、加工组织和存储设计数据,从而一方面简化设计流程,提高团队设计效率;另一方面通过计算机完成繁琐的计算和数据处理工作,减轻设计人员的工作负荷,减少数据     

雷达抗干扰能力指标测试环境设计

雷达抗干扰能力指标测试环境设计,主要内容包括雷达回波模拟目标信号设计和干扰信号设计。重点解决两个问题:对于目标信号设计,确定模拟目标信号模型;对于干扰信号设计,提出干扰信号的时间分布设计、空间分布设计和频域分布设计。目的是为抗干扰能力指标测试的典型信号环境设计提供技术基础,提高电子干扰环境科学设计与生成能力。干扰测试环境设计技术已得到部分应用,具有可持续应用研究价值。     

略论商品包装装潢设计的人性化内涵

满足人性化需求是包装设计的最终目标。在现代设计中,无论那个领域的设计都强调环境的保护,资源的再利用,强调人性化,以人为本。论文就商品包装装潢设计的美学追求、适应消费心理、体现民族风格、通用化设计、适度化设计、绿色包装设计等要素对包装装潢设计的人性化进行了探讨和研究。     

扁平化——UI领域的简约主义

扁平化设计(Flat Design)风格是当下非常流行的,以简约主义为核心的设计理念,它已然成为UI(User Interface)设计的主流风格。本文由简约主义开始谈起,从扁平化设计的内涵、优缺点、设计方法及UI设计的终极目标等方面阐述了笔者对扁平化设计风格的理解。     

面向效能的精确制导武器设计技术初探

针对以“性能”为核心的设计不能满足信息化战争对精确制导武器研制提出的设计需求的问题,初步探讨了面向效能的精确制导武器设计技术。首先分析了国内外精确制导武器设计技术的发展,指出精确制导武器的设计技术向着以“效能为核心”的设计方向发展;其次分析了信息化条件下精确制导武器设计的六条基本原则;接着以这些原则为基础提出面向效能的精确制导武器设计理念,分析指出面向效能的设计是以追求满意设计为目标的优化设计;然后在新的设计理念的指导下提出了面向效能设计的技术框架,主要说明了面向效能的精确制导武器设计框架、效能基础、技术基础、基本模式和三项关键技术等;最后探讨了面向效能的精确制导武器设计方法的四个方面：模块化、智能化、通用技术的集成和信息通道的多元化。     

基于权衡空间探索的多约束弹道初值确定方法

运载火箭弹道设计对初值的选取敏感,需要设计人员具备相应经验,新构型或新任务下迭代设计易发散,设计过程依靠人员手动调整,效率较低。应用权衡空间探索及全局优化思想,给出了多约束弹道设计初值确定方法,并在此基础上重新建立了弹道设计流程,自动完成初值选取及精确设计,降低了设计过程对人员经验的依赖性,提升了弹道设计方法的智能化程度,提高了论证及设计效率。     

型号设计中的安全性设计分析

通过对“长征三号”运载火箭的一些安全性设计实例帕的分析来建立安全性设计的概念，论述安全性设计在型号设计中的重要作用和地位。分析认为，安全性设计应以总体、系统设计师为主，并从设计初期抓起。     

对提高空间遥感载荷设备设计质量的探究

只有开展健壮设计，提高设计质量，才能从根本上提高产品质量。本文通过对健壮设计方法体系中典型、有代表性的系统设计方法，参数设计方法，设计FMEA方法的应用情况分析，表明只有根据产品各个设计阶段工作的侧重点及特点，并结合本单位的实际情况，合理地选择一种设计方法，或者几种设计方法交互使用，才能取得令人满意的效果。要持之以恒地学习和研究先进的、科学的、有效的设计方法，推广应用到产品的设计中去，以提高设计质量。     

Importance of a martian hematite site for astrobiology

Defining locations where conditions may have been favorable for life is a key objective for the exploration of Mars. Of prime importance are sites where conditions may have been favorable for the preservation of evidence of prebiotic or biotic processes. Areas displaying significant concentrations of the mineral hematite (alpha-Fe2O3), recently identified by thermal emission spectrometry, may have significance in the search for evidence of extraterrestrial life. Since iron oxides can form as aqueous mineral precipitates, the potential exists to preserve microscopic evidence of life in iron oxide-depositing ecosystems. Terrestrial hematite deposits proposed as possible analogs for hematite deposits on Mars include massive (banded) iron formations, iron oxide hydrothermal deposits, iron-rich laterites and ferricrete soils, and rock varnish. We report the potential for long-term preservation of microfossils by iron oxide mineralization in specimens of the approximately 2,100-Ma banded iron deposit of the Gunflint Formation, Canada. Scanning and analytical electron microscopy reveals micrometer-scale rods, spheres, and filaments consisting predominantly of iron and oxygen with minor carbon. We interpret these objects as microbial cells permineralized by an iron oxide, presumably hematite. The confirmation of ancient martian microbial life in hematite deposits will require the return of samples to terrestrial laboratories. A hematite-rich deposit composed of aqueous iron oxide precipitates may thus prove to be a prime site for future sample return.     

Ultrastructural study of iron oxide precipitates: implications for the search for biosignatures in the Meridiani hematite concretions, Mars

Two terrestrial environments that have been proposed as analogs for the iron oxide precipitation in the Meridiani Planum region of Mars include the Rio Tinto precipitates and southern Utah marble concretions. Samples of two typical Utah iron oxide concretions and iron oxide precipitates in contact with biofilms from Rio Tinto have been studied to determine whether evidence could be found for biomediation in the precipitation process and to identify likely locations for fossil microorganisms. Scanning electron microscopy, energy dispersive X-ray, and gas chromatography-mass spectrometry (GC-MS) were used to search for biosignatures in the Utah marbles. The precipitation of iron oxides resembles known biosignatures, though organic compounds could not be confirmed with GC-MS analysis. In contrast, textural variations induced by biological activity are abundant in the modern Rio Tinto samples. Although no compelling evidence of direct or indirect biomediation was found in the Utah marbles, the ultrastructure of the iron oxide cement in the concretion suggests an inward growth during concretion precipitation from an initially spherical redox front. No indication for growth from a physical nucleus was found.     

Iron-scytonemin complexes: DFT calculations on new UV protectants for terrestrial cyanobacteria and astrobiological implications

Cyanobacterial colonies produce the radiation-protectant biomolecule scytonemin as part of their response strategy for survival in environmentally stressed conditions in hot and cold deserts. These colonies frequently use sandstone rocks as host matrices for subsurface colonization, which is accompanied by a zone of depletion of iron and transportation of iron compounds to the mineral surface. It is suggested that an iron-scytonemin complex could feature in this survival strategy and facilitate the movement of iron through the rock. Calculations were carried out on several hypothetical iron-scytonemin complexes to evaluate the most stable structure energetically and examine the effect of the complexation of the biomolecule upon the electronic absorption characteristics of the radiation-protectant species. The implications for extraterrestrial planetary detection and analytical monitoring of an iron-scytonemin complex are assessed.     

Stable iron isotopes and microbial mediation in red pigmentation of the Rosso Ammonitico (mid-late Jurassic, Verona area, Italy)

The iron (Fe) isotopic composition of 17 Jurassic limestones from the Rosso Ammonitico of Verona (Italy) have been analyzed by Multiple-Collector Inductively Coupled Plasma Mass Spectrometry (MC-ICP-MS). Such analysis allowed for the recognition of a clear iron isotopic fractionation (mean -0.8 per thousand, ranging between -1.52 to -0.06 per thousand) on a millimeter-centimeter scale between the red and grey facies of the studied formation. After gentle acid leaching, measurements of the Fe isotopic compositions gave delta(56)Fe values that were systematically lower in the red facies residues (median: -0.84 per thousand, range: -1.46 to +0.26 per thousand) compared to the grey facies residues (median: -0.08 per thousand, range: -0.34 to +0.23 per thousand). In addition, the red facies residues were characterized by a lighter delta(56)Fe signal relative to their corresponding leachates. These Fe isotopic fractionations could be a sensitive fingerprint of a biotic process; systematic isotopic differences between the red and grey facies residues, which consist of hematite and X-ray amorphous iron hydroxides, respectively, are hypothesized to have resulted from the oxidizing activity of iron bacteria and fungi in the red facies. The grey Fe isotopic data match the Fe isotopic signature of the terrestrial baseline established for igneous rocks and low-C(org) clastic sedimentary rocks. The Fe isotopic compositions of the grey laminations are consistent with the influx of detrital iron minerals and lack of microbial redox processes at the water-interface during deposition. Total Fe concentration measurements were performed by Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-AES) (confirmed by concentration estimations obtained by MC-ICP-MS analyses of microdrilled samples) on five samples, and resultant values range between 0.30% (mean) in the grey facies and 1.31% (mean) in the red facies. No correlation was observed between bulk Fe content and pigmentation or between bulk Fe content and Fe isotopic compositions. The rapid transformation of the original iron oxyhydroxides to hematite could have preserved the original isotopic composition if it had occurred at about the same temperature. This paper supports the use of Fe isotopes as sensitive tracers of biological activities recorded in old sedimentary sequences that contain microfossils of iron bacteria and fungi. However, a careful interpretation of the iron isotopic fractionation in terms of biotic versus abiotic processes requires supporting data or direct observations to characterize the biological, (geo)chemical, or physical context in relation to the geologic setting. This will become even more pertinent when Fe isotopic studies are expanded to the interplanetary realm.     

Meteoritic steel as a construction resource on Mars

In the long term, settlement of Mars will require local refining of industrial and construction materials. One of the most significant industrial materials is steel. It is proposed that steel can be harvested on Mars in the form of reduced iron available on the surface from meteoric nickel–iron. This may be one of the most easily available resources on Mars.     

Olivine-respiring bacteria isolated from the rock-ice interface in a lava-tube cave, a Mars analog environment

The boundary between ice and basalt on Earth is an analogue for some near-surface environments of Mars. We investigated neutrophilic iron-oxidizing microorganisms from the basalt-ice interface in a lava tube from the Oregon Cascades with perennial ice. One of the isolates (Pseudomonas sp. HerB) can use ferrous iron Fe(II) from the igneous mineral olivine as an electron donor and O(2) as an electron acceptor. The optimum growth temperature is ～12-14°C, but growth also occurs at 5°C. Bicarbonate is a facultative source of carbon. Growth of Pseudomonas sp. HerB as a chemolithotrophic iron oxidizer with olivine as the source of energy is favored in low O(2) conditions (e.g., 1.6% O(2)). Most likely, microbial oxidation of olivine near pH 7 requires low O(2) to offset the abiotic oxidation of iron. The metabolic capabilities of this bacterium would allow it to live in near-surface, icy, volcanic environments of Mars in the present or recent geological past and make this type of physiology a prime candidate in the search for life on Mars.     

活笥银粉中微量铜铁的测定

提出用空气－乙炔火焰原子吸收光谱法来测定银锌电池活性银粉中的微量铜铁，并对测定条件和干扰因素进行了综合考虑，该测定方法具有灵敏度、精确度高，干扰小，选择性和重现性好等优点。测定样品微量铜铁含量的相对标准偏差均小于１.5%(n=8）。标准加入回收率均在（９７.00-102.00)%(n=5)范围内，完全适用于银锌电池活性银粉中微量铜铁含量的控制和样品系统分析，实际应用中取得了很好的效果。     

Iron meteorites can support the growth of acidophilic chemolithoautotrophic microorganisms

Chemolithoautotrophy based on reduced inorganic minerals is considered a primitive energy transduction system. Evidence that a high number of meteorites crashed into the planet during the early period of Earth history led us to test the ability of iron-oxidizing bacteria to grow using iron meteorites as their source of energy. Here we report the growth of two acidophilic iron-oxidizing bacteria, Leptospirillum ferrooxidans and Acidithiobacillus ferrooxidans, on a piece of the Toluca meteorite as the only source of energy. The alteration of the surface of the exposed piece of meteorite, the solubilization of its oxidized metal constituents, mainly ferric iron, and the formation of goethite precipitates all clearly indicate that iron-meteorite-based chemolithotrophic metabolism is viable.     

Formation of nucleobases from formamide in the presence of iron oxides: implication in chemical evolution and origin of life

Simple compounds like HCN, which have one C and one N, are proposed as the probable precursors for biomonomers. Formamide, a hydrolysis product of HCN, is known as the precursor of various biologically important compounds, for example, nucleobases (purines and pyrimidines). In this paper, we report our results on the synthesis of nucleobases, adenine, cytosine, purine, 9-(hydroxyacetyl) purine, and 4(3H)-pyrimidinone from formamide, using iron oxide (hematite) and oxide hydroxides (goethite and akaganeite) as a catalyst. Goethite and hematite produced purine in higher yield. The products formed were characterized by high-performance liquid chromatography and electrospray ionization mass spectrometry techniques. Results of our study reveal that iron oxides might have worked as efficient prebiotic catalysts.     

Effects of HZE particle on the nigrostriatal dopaminergic system in a future Mars mission

Because of long duration travel outside the Earth's magnetic field, the effect of iron-rich high charge and energy (HZE) particles in Galactic Cosmic Rays on human body is the major concern in radiation protection. Recently attention has been directed to effects on the central nervous system in addition to mutagenic effects. In particular, a reduction in striatal dopamine content on nigrostriatal dopaminergic system has been reported by investigators using accelerated iron ions in ground-based mammalian studies. In addition, studies of the pathophysiology of Parkinson's disease demonstrated that excess iron cause a reduction in the dopamine content in the substantia nigra. This suggests an intriguing possibility to explain the selective detrimental effects of HZE particles on the dopaminergic system. Should these particles have biochemical effects, possible options for countermeasures are: (1) nutritional prevention, (2) medication, and (3) surgical placement of a stimulator electrode at a specific anatomic site in the basal ganglia.