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Importance of hydrogenotrophic, aceticlastic and methylotrophic methanogenesis for methane production in terrestrial, aquatic and other anoxic environments: A mini review

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Pedosphere 2020年第1期30卷 25-39页

作者： ralf CONRAD Max Planck Institute for Terrestrial Microbiology Karl-von-Frisch-Str.10Marburg 35043(Germany)

Microbial methanogenesis is a major source of the greenhouse gas methane(CH4).It is the final step in the anaerobic degradation of organic matter when inorganic electron acceptors such as nitrate,ferric iron,or sulfate have been *** of this degradation pathway is important for the creation of mechanistic models,prediction of future CH4 emission scenarios,and development of mitigation *** most anoxic environments,CH4 is produced from either acetate(aceticlastic methanogenesis)or hydrogen(H2)plus carbon dioxide(CO2)(hydrogenotrophic methanogenesis).Hydrogen can be replaced by other CO2-type methanogenesis,using formate,carbon monoxide(CO),or alcohols as *** ratio of these two pathways is tightly constrained by the stoichiometry of conversion *** the degradation of organic matter is complete(e.g.,degradation of straw in rice paddies),then fermentation eventually results in production of acetate and H2 at a ratio of>67%aceticlastic and<33%hydrogenotrophic ***,acetate production can be favored when heterotrophic or chemolithotrophic acetogenesis is enhanced,and H2 production can be favored when syntrophic acetate oxidation is *** typically occurs at low and elevated temperatures,***,temperature can strongly influence the methanogenic pathway,which may range from 100%aceticlastic methanogenesis at low temperatures to 100%hydrogenotrophic methanogenesis at high ***,if the degradation of organic matter is not complete(e.g.,degradation of soil organic matter),the stoichiometry of fermentation is not tightly constrained,resulting,for example,in the preferential production of H2,followed by hydrogenotrophic *** production of CH4 by either aceticlastic or hydrogenotrophic methanogenesis can also happen if one of the methanogenic substrates is not consumed by methanogens but is,instead,accumulated,volatilized,or utilized *** methano

关键词： electron acceptor fermentation methanogenic pathway organic matter degradation pH soil microbial community temperature Wood-Ljungdahl pathway

Micro/nano multiscale reinforcing strategies toward extreme high-temperature applications:Take carbon/carbon composites and their coatings as the examples

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Journal of Materials Science & Technology 2022年第1期96卷 31-68页

作者： Qiangang Fu Pei Zhang Lei Zhuang Lei Zhou Jiaping Zhang Jie Wang Xianghui Hou ralf Riedel Hejun Li State Key Laboratory of Solidification Processing Shaanxi Key Laboratory of Fiber Reinforced Light Composite MaterialsCarbon/Carbon Composites Research CenterNorthwestern Polytechnical UniversityXi’an 710072China School of Materials Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China Faculty of Engineering University of NottinghamUniversity ParkNottingham NG72RDUnited Kingdom Institut für Materialwissenschaft Technische Universität DarmstadtOtto-Berndt-Straße 3Darmstadt D-64287Germany

Carbon fiber reinforced carbon composites(C/Cs),are the most promising high-temperature materials and could be widely applied in aerospace and nucleation fields,owing to their superior ***,C/Cs are very susceptible to destructive oxidation and thus fail at elevated *** matrix modification and coating technologies with Si-based and ultra-high temperature ceramics(UHTCs)are valid to enhance the oxidation/ablation resistance of C/Cs,it’s not sufficient to satisfy the increasing practical applications,due to the inherent brittleness of ceramics,mismatch issues between coatings and C/C substrates,and the fact that carbonaceous matrices are easily prone to high-temperature *** effectively solve the aforementioned problems,micro/nano multiscale reinforcing strategies have been developed for C/Cs and/or the coatings over the past two decades,to fabricate C/Cs with high strength and excellent high-temperature *** review is to systematically summarize the most recent major and important advancements in some micro/nano multiscale strategies,including nanoparticles,nanowires,carbon nanotubes/fibers,whiskers,graphene,ceramic fibers and hybrid micro/nano structures,for C/Cs and/or the coatings,to achieve high-temperature oxidation/ablation-resistant C/***,this review is concluded with an outlook of major unsolved problems,challenges to be met and future research advice for C/Cs with excellent comprehensive mechanical-thermal ***’s hoped that a better understanding of this review will be of high scientific and industrial interest,since it provides unusual and feasible new ideas to develop potential and practical C/Cs with improved high-temperature mechanical and oxidation/ablation-resistant properties.

关键词： Carbon/carbon composites Micro/nano multiscale reinforcing strategies Oxidation Ablation Erosion Hybrid structures

Composition-dependent structural characteristics and mechanical properties of amorphous SiBCN ceramics by ab-initio calculations

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Journal of Advanced Ceramics 2023年第5期12卷 984-1000页

作者： Yuchen Liu Yu Zhou Dechang Jia Zhihua Yang Wenjiu Duan Daxin Li Shuzhou Li ralf Riedel Bin Liu Institute for Advanced Ceramics School of Materials Science and EngineeringHarbin Institute of TechnologyHarbin 150001China School of Materials Science and Engineering Shanghai UniversityShanghai 200444China Tsinghua Shenzhen International Graduate School Tsinghua UniversityShenzhen 518055China School of Materials Science and Engineering Nanyang Technological UniversitySingapore 639798Singapore Institut für Materialwissenschaft Technische Universität DarmstadtDarmstadt D-64287Germany

The atomic structural features and the mechanical properties of amorphous silicoboron carbonitride ceramics with 13 different compositions in the Si–BN–C phase diagram are investigated employing ab-initio *** chemical bonds and local structures within the amorphous network relate to the elemental *** distribution of nine types of chemical bonds is composition-dependent,where the B–C,Si–N,Si–C,and B–N bonds hold a large proportion for all *** prefers to be tetrahedrally coordinated,while B and N prefer sp^(2)-like trigonal *** the case of C,the tetrahedral coordination is predominant at relatively low C contents,while the trigonal coordination is found to be the main feature with the increasing C *** local structural characteristics greatly influence the mechanical properties of SiBCN *** the studied amorphous ceramics,SiB_(2)C_(3)N_(2) and SiB_(3)C_(2)N_(3) with low Si contents and moderate C and/or BN contents have high elastic moduli,high tensile/shear strengths,and good debonding *** increment of Si,C,and BN contents on this basis results in the decrease of mechanical *** increasing Si content leads to the increment of Si-contained bonds that reduce the bond strength of SiBCN ceramics,while the latter two cases are attributed to the raise of sp^(2)-like trigonal configuration of C and *** discoveries are expected to guide the composition-tailored optimization of SiBCN ceramics.

关键词： ultra-high-temperature ceramics density functional theory(DFT) amorphous structure mechanical properties

Sperm preparation： state-of-the-art--physiological aspects and application of advanced sperm preparation methods

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Asian Journal of Andrology 2012年第2期14卷 260-269页

作者： ralf Henkel Department of Medical Biosciences University of the Western Cape Bellville 7535 South Africa

For assisted reproduction technologies （ART）, numerous techniques were developed to isolate spermatozoa capable of fertilizing oocytes. While early methodologies only focused on isolating viable, motile spermatozoa, with progress of ART, particularly intracytoplasmic sperm injection （ICSI）, it became clear that these parameters are insufficient for the identification of the most suitable spermatozoon for fertilization. Conventional sperm preparation techniques, namely, swim-up, density gradient centrifugation and glass wool filtration, are not efficient enough to produce sperm populations free of DNA damage, because these techniques are not physiological and not modeled on the stringent sperm selection processes taking place in the female genital tract. These processes only allow one male germ cell out of tens of millions to fuse with the oocyte. Sites of sperm selection in the female genital tract are the cervix, uterus, uterotubal junction, oviduct, cumulus oophorus and the zona pellucida. Newer strategies of sperm preparation are founded oni （i） morphological assessment by means of＇motile sperm organelle morphological examination （MSOM E）＇; （ii） electrical charge; and （ili） molecular binding characteristics of the sperm cell. Whereas separation methods based on electrical charge take advantage of the sperm＇s adherence to a test tube surface or separate in an electrophoresis, molecular binding techniques use Annexin V or hyaluronic acid （HA） as substrates. Techniques in this category are magnet-activated cell sorting, Annexin V-activated glass wool filtration, flow cytometry and picked spermatozoa for ICSI （PICSI） from HA-coated dishes and HA-containing media. Future developments may include Raman microspectrometry, confocal light absorption and scattering spectroscopic microscopy and polarization microscopy.

关键词： advanced sperm selection biomimetics conventional sperm selection female genital tract physiological sperm selection

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基于电阻器耦合的电动汽车感应充电定位

同济大学学报（自然科学版） 2022年第S1期50卷 165-169页

作者： ralf SAUERWALD Lukas BRANDL Hans-Christian REUSS 斯图加特大学汽车工程学院(IFS) 德国斯图加特70569

目前,市场上出现越来越多的以电池为动力的电动汽车,其中大多数电动汽车必须通过有线充电装置进行充电。与之相对应的感应式无线充电系统,可以让充电过程更加舒适。无线充电系统一般由初级线圈和次级线圈组成,其中初级线圈可以建立在停... 详细信息

目前,市场上出现越来越多的以电池为动力的电动汽车,其中大多数电动汽车必须通过有线充电装置进行充电。与之相对应的感应式无线充电系统,可以让充电过程更加舒适。无线充电系统一般由初级线圈和次级线圈组成,其中初级线圈可以建立在停车场,将电能转化为场能;次级线圈安装在车辆中,接收初级线圈能量并转化为电能,为车辆电池充电。为保证充电过程安全有效,初级线圈和次级线圈必须充分耦合,这可通过将车辆准确定位在初级线圈上方来实现。本文提出了一种简单而经济的方法来验证线圈之间的耦合是否足以满足充电条件。通过安装在次级线圈侧的电阻,来模拟在确定工作条件下无线充电系统的电池负载;电阻两端电压可以用来估计线圈之间的耦合度,以反映车辆与初级线圈的相对位置。本文在数学和物理原理的基础上解释了这个概念,并在一个真实的无线电传输线路上进行了试验评估。

关键词：电动汽车无线动力充电联轴器定位

数据保护权是一项权利吗——基于欧盟和美国的考察

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苏州大学学报（法学版） 2024年第2期11卷 153-160页

作者： [德]拉尔夫·波歇尔周遵友(译) 余云霞(译) 德国马克斯·普朗克犯罪、安全与法律研究所中南民族大学法学院

数据保护权关注的是与个人数据之使用相关的抽象危险,而这些危险往往会对诸如结社、言论自由等其他基本权利造成侵犯。因此,数据保护权本身不是一项独立的基本权利,而是对其他受到宪法保障的权利和自由的预防性提升,这种看待数据保护的... 详细信息

数据保护权关注的是与个人数据之使用相关的抽象危险,而这些危险往往会对诸如结社、言论自由等其他基本权利造成侵犯。因此,数据保护权本身不是一项独立的基本权利,而是对其他受到宪法保障的权利和自由的预防性提升,这种看待数据保护的方式也能得到相关司法判例的支持,而且能够更好地解释数据保护与其他权利的关系。认定数据保护并非一项权利,具有重要的现实意义,根据这种理论形成的方法,相较于目前正在德国和欧洲盛行的方法更加具有系统性,这一新视角不仅关注个人数据的收集,还考虑到了整个数据处理系统及其环境,有助于我们更好地理解大西洋两岸在数据保护标准方面的差异。

关键词：数据保护权基本权利隐私权信息自决权

反射激波与边界层相互作用引起弱点火和强点火的数值研究

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Acta Mechanica Sinica 2022年第2期38卷 24-34,I0001页

作者：黄成扬王元 Deiterding ralf 于德海陈正 SKLTCS CAPTCollege of EngineeringPeking UniversityBeijing 100871China Institute of Applied Physics ami Computational Mathematics Beijing 100094China Aerochnamics and Flight Mechanics Research Group University of SouthamptonHighfield CampusSouthampton SO171BJUK

在激波管实验中,反射激波与边界层的相互作用会导致激波分义和弱点火.在激波管实验中,弱点火会严重影响点火延迟时间的测量.在考虑详细的化学和输运效应下,本文通过二维数值模拟研究反射激波后的激波分岔和非均匀点火,以解释反射激波和... 详细信息

在激波管实验中,反射激波与边界层的相互作用会导致激波分义和弱点火.在激波管实验中,弱点火会严重影响点火延迟时间的测量.在考虑详细的化学和输运效应下,本文通过二维数值模拟研究反射激波后的激波分岔和非均匀点火,以解释反射激波和边界层相互作用引发激波分岔的形成机理,并研究氢和二甲醚的弱点火及其向强点火的转变.研究发现入射激波在端壁的非均匀反射会在壁面产生一个楔形斜激波脚.楔形结构导致反射激波和边界层之间的强烈相互作用,从而导致激波分岔.结果表明分叉激波底部的局部高温点产生于黏性耗散和压力功.随着反射后激波温度的升高,在化学计量氢/氧混合物中观察到从弱点火到强点火的转变.通过引入点火延迟时间对反射后激波温度的相对灵敏度,可以表征反射激波后弱点火出现.与氢/氧混合物不同,在二甲醚/氧混合物中未观察到弱点火现象,因为其具有相对较长的点火延迟时间和较小的相对灵敏度.

关键词：点火延迟时间化学计量相对灵敏度分岔入射激波反射激波楔形结构激波管实验

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基于横向磁通电机的派生能量收集研究

同济大学学报（自然科学版） 2022年第S1期50卷 181-185页

作者： Lukas BRANDL ralf SAUERWALD Hans-Christian REUSS 斯图加特大学汽车工程学院(IFS) 德国斯图加特70569

为了监测汽车电机的工作情况需要应用各类传感器,其中的挑战之一是为在旋转部件上布置的传感器提供电能。通过使用能量收集器,可以将电机中的寄生能量如电磁能和动能收集、转化为电能并储存,存储的电能可用来操作传感器。因此,本文以电... 详细信息

为了监测汽车电机的工作情况需要应用各类传感器,其中的挑战之一是为在旋转部件上布置的传感器提供电能。通过使用能量收集器,可以将电机中的寄生能量如电磁能和动能收集、转化为电能并储存,存储的电能可用来操作传感器。因此,本文以电机转子为重点,对一台横向磁通机进行研究,其中能量收集器用于收集足够的能量,并为一个温度传感器以及低功耗蓝牙非接触数据传输供电。为此,本文计算了当能量收集器被放置在横向磁通电机转子上时,在运行和生产过程中可望收集到的能量值。

关键词：自供能传感器能量收集电动机

Leukocytes and oxidative stress： dilemma for sperm Function and male fertility

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Asian Journal of Andrology 2011年第1期13卷 43-52页

作者： ralf R Henkel Department of Medical Biosciences University of the Western Cape Bellville 7535 South Africa

Spermatozoa are constantly exposed to the interphase between oxidation through high amounts of reactive oxygen species （ROS） and leukocytes, and reduction by means of scavengers and antioxidants. Considering the very special functions as being the only cells with such high polarization and exerting their functions outside the body, even in a different individual, the female genital tract, the membranes of these cells are chemically composed of an extraordinary high amount of polyunsaturated fatty acids. This in turn, renders them very susceptible to oxidative stress, which is defined as an imbalance between oxidation and reduction towards the oxidative status. As a result, ROS deriving from both leukocytes and the male germ cells themselves cause a process called ＇lipid peroxidation＇ and other damages to the sperm cell. On the other hand, a certain limited amount of ROS iS essential in order to trigger vital physiological reactions in cells, including capacitation or the acrosome reaction in sperm. The treatment of patients with antioxidants to compensate the oxidative status caused by oxidative stress is highly debated as uncontrolled antioxidative treatment might derail the system towards the reduced status, which is also unphysiological and can even induce cancer. This paradox is called the ＇antioxidant paradox＇. Therefore, a proper andrological diagnostic work-up, including the evaluation of ROS levels and the antioxidant capacity of the semen, has to he carried out beforehand, aimed at keeping the fine balance between oxidation and scavenging of vital amounts of ROS.

关键词： antioxidants balance beneficial effects detrimental effects leukocytes male infertility reactive oxygen species sperm functions