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排序方式: 共有626条查询结果,搜索用时 15 毫秒
1.
Rebecca L. Tarnopol Sierra Bowden Kevin Hinkle Krithika Balakrishnan Akira Nishii Caleb J. Kaczmarek Tara Pawloski Dr. Anthony G. Vecchiarelli 《Chembiochem : a European journal of chemical biology》2019,20(20):2535-2545
One of the primary challenges facing synthetic biology is reconstituting a living system from its component parts. A particularly difficult landmark is reconstituting a self-organizing system that can undergo autonomous chromosome compaction, segregation, and cell division. Here, we discuss how the syn3.0 minimal genome can inform us of the core self-organizing principles of a living cell and how these self-organizing processes can be built from the bottom up. The review underscores the importance of fundamental biology in rebuilding life from its molecular constituents. 相似文献
2.
Mine Water and the Environment - Artisanal and small-scale mining (ASM) of gold has adversely affected the environment and human health for decades, mostly due to excessive use of mercury. With the... 相似文献
3.
Saunders Ben Camgoz Necati Cihan Bowden Richard 《International Journal of Computer Vision》2021,129(7):2113-2135
International Journal of Computer Vision - Sign languages are multi-channel visual languages, where signers use a continuous 3D space to communicate. Sign language production (SLP), the automatic... 相似文献
4.
Antibacterial activity against Escherichia coli of Cu‐BTC (MOF‐199) metal‐organic framework immobilized onto cellulosic fibers 下载免费PDF全文
Haendel S. Rodríguez Juan P. Hinestroza Cristian Ochoa‐Puentes Cesar A. Sierra Carlos Y. Soto 《应用聚合物科学杂志》2014,131(19)
A strong antimicrobial activity against Escherichia coli of Cu‐BTC metal‐organic frameworks immobilized over cellulosic fibers is hereby reported. The in situ synthesis of Cu‐BTC metal‐organic frameworks, aka MOF‐199 or HKUST‐1, onto cellulosic substrates was carried out by exposing carboxymethylated cellulosic substrates to Cu(OAC)2, 1,3,5‐benzenetricarboxylic acid and triethylamine solutions following a very specific order. Using an in vitro model, in accordance to ASTM E2149‐13a, we observed that the cellulose‐MOF system was able to completely eliminate the growth of E. coli on agar plates and liquid cultures. The antibacterial activity of the comprising components of MOF‐199 and the cellulosic substrate was also evaluated and determined to be negligible. Since the method used to synthesize MOF‐199 crystals provides a strong bond between the crystals and the cellulosic substrates, the crystals not detach from the anionic cellulosic fibers allowing the modified textile to be washed and reused hence opening a new avenue to fabricate antibacterial clinical fabrics. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40815. 相似文献
5.
Unai Iriarte‐Velasco Irene Sierra Emilio Atilano Cepeda Raquel Bravo Jose Luis Ayastuy 《Coloration Technology》2015,131(4):322-332
Bone is an inorganic template containing organic material inside which can be converted into hydroxyapatite‐rich material by pyrolysis. Nowadays, there is a growing research interest in the use of hydroxyapatite, the chemical formula of which is Ca10(PO4)6(OH)2. In the present work, pork bone, an abundant biomass source and food waste, has been converted into structured porous hydroxyapatite by a three‐step process including precharring under mild conditions, chemical activation, and thermal activation. The investigated activating agents were NaOH, KOH, K2CO3, H2SO4, and H3PO4. A thorough investigation of the influence of different activating protocols on the chemical and textural properties of the produced material was carried out by nitrogen adsorption–desorption at 77 K, potentiometric titrations, Fourier transform infrared, and X‐ray diffraction techniques. Chemical activation with NaOH, K2CO3, and H2SO4 increased the specific surface area up to 53%. H3PO4 reduced both surface area and pore volume, and KOH showed little influence on the pore structure. The produced materials were evaluated by methylene blue adsorption tests and showed significant improvement as a result of chemical activation. As a main effect, acid treatment increased methylene blue adsorption kinetics, probably owing to an increase in micropororosity, whereas alkali activation enhanced the adsorption capacity of the resultant biochar. 相似文献
6.
7.
Continuous removal and recovery of palladium in an upflow anaerobic granular sludge bed (UASB) reactor 下载免费PDF全文
8.
Susana Ferreiro Basilio Sierra 《The International Journal of Advanced Manufacturing Technology》2012,60(1-4):237-249
This paper presents a particular problem dealing with the apparition of burr during the drilling process in the aeronautic industry. This burr cannot exceed a height limit of 127?μm as set out by the aeronautical guidelines and must be eliminated before riveting. If this is not performed, it can cause structural damage which would constitute a danger due to the lack of safety. Moreover, the industry needs to find an automated and optimised process in which the drilling and deburring can be carried out in real time, eliminating those other unnecessary tasks, in order to obtain high-quality pieces. The work presents the applicability of data mining and machine learning techniques so as to obtain a real time burr detection model. This model could be implanted in the computer numerical control of the machine allowing the whole process to be automated and optimised. These techniques can be applied to other types of processes. 相似文献
9.
O. Kirichek A.J. Church M.G. Thomas D. Cowdery S.D. Higgins M.P. Dudman Z.A. Bowden 《低温学》2012,52(7-9):325-330
Adhesion and plasticity of polycrystalline solid methane have been studied in the temperature range 10–90 K. It was shown that adhesion is very strong in the 50–90 K temperature range where the solid methane is soft and sticky. Closer to the melting point (at 90.6 K) the solid methane behaves as extremely viscous non-Newtonian liquid. Below 30 K solid methane loses its stickiness and ductility and acts like ordinary glass. Methane adhesion remains similar for very different materials. We have also made some video observations which reveal unexpected and mostly inexplicable properties of solid methane which could be of some interest for designing new methane moderators for neutron sources and planetary physics particularly the study of the environment of Titan. 相似文献
10.
J.M. Sierra S.J. Figueroa-Ramírez S.E. Díaz J. Vargas P.J. Sebastian 《International Journal of Hydrogen Energy》2014
In this research a 3D numerical study on a PEM fuel cell model with tubular plates is presented. The study is focused on the performance evaluation of three flow fields with cylindrical geometry (serpentine, interdigitated and straight channels) in a fuel cell. These designs are proposed not only with the aim to reduce the pressure losses that conventional designs exhibit with rectangular flow fields but also to improve the mass transport processes that take place in the fuel cell cathode. A commercial computational fluid dynamics (CFD) code was used to solve the numerical model. From the numerical solution of the fluid mechanics equations and the electrochemical model of Butler-Volmer different analysis of pressure losses, species concentration, current density, temperature and ionic conductivity were carried out. The results were obtained at the flow channels and the catalyst layers as well as in the gas diffusion layers and the membrane interfaces. Numerical results showed that cylindrical channel configurations reduced the pressure losses in the cell due to the gradual reduction of the angle at the flow path and the twist of the channel, thus facilitating the expulsion of liquid water from the gas diffusion layers and in turn promoting a high oxygen concentration at the triple phase boundary of the catalyst layers. Moreover, numerical results were compared to polarization curves and the literature data reported for similar designs. These results demonstrated that conventional flow field designs applied to conventional tubular plates have some advantages over the rectangular designs, such as uniform pressure and current density distributions among others, therefore they could be considered for fuel cell designs in portable applications. 相似文献