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Nano Research 2022年第5期15卷 4500-4516页

作者： Aleksei Llusco luis Rojas Svetlana Ushak Mario Grageda Department of Chemical Engineering and Mineral Processing and Center for Advanced Study of Lithium and Industrial Minerals(CELiMIN) Universidad de AntofagastaAntofagasta 1270300Chile

Potential advantages of active electrode nanomaterials have led to development of high energy and power density lithium-ion(Li-ion)***,under increasing demand for critical resources such as lithium and cobalt,it is necessary to use abundant raw materials,which can be obtained from industrial *** this work,purified Mg(OH)_(2)from waste generated in the production of Li2CO3 with natural brines from the Salar de Atacama(Chile)is used as a doping agent for synthesis of LiMn_(2)O_(4)(LMO)spinel octahedral nanoparticles co-doped with excess Li and *** of a pure cubic spinel phase(Fd3m)takes place at 500℃and sintering temperature effect at 580 and 750℃,thus the elemental composition and the structural,morphological,and electrochemical properties are studied in *** electrochemical performance at room temperature is obtained for Li_(1.03)Mg_(0.05)Mn_(1.92)O_(4)spinel sintered at 750℃with an initial discharge capacity of 121.3 mAh·g^(-1)and capacity retention of 94.0%after 100 cycles at C/3.A locally ordered spinel structure is obtained at 750℃,and doping with Mg^(2+)improves structural *** between both effects resulted in a high Li^(+)diffusion rate(1.29×10^(-9)cm^(2)·s^(-1))significantly improving cycling performance at elevated C-rates in 50℃.

关键词： LiMn_(2)O_(4)(LMO)spinel Mg doped excess Li octahedral nanoparticle industrial waste lithium-ion(Li-ion)batteries

Additives in metal halide perovskite films and their applications in solar cells

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Journal of Energy Chemistry 2020年第7期29卷 215-228,I0007页

作者： Zonghao Liu luis K.Ono Yabing Qi Energy Materials and Surface Sciences Unit(EMSSU) Okinawa Institute of Science and Technology Graduate University(OIST)Okinawa 904-0495Japan

The booming growth of organic-inorganic hybrid lead halide perovskite solar cells have made this promising photovoltaic technology to leap towards *** of the most important issues for the evolution from research to practical application of this technology is to achieve high-throughput manufacturing of large-scale perovskite solar *** particular,realization of scalable fabrication of large-area perovskite films is one of the essential *** the past ten years,a great number of approaches have been developed to deposit high quality perovskite films,to which additives are introduced during the fabrication process of perovskite layers in terms of the perovskite grain growth control,defect reduction,stability enhancement,***,we first review the recent progress on additives during the fabrication of large area perovskite films for large scale perovskite solar cells and *** then focus on a comprehensive and in-depth understanding of the roles of additives for perovskite grain growth control,defects reduction,and stability *** advancement of the scalable fabrication of high-quality perovskite films and solar cells using additives to further develop large area,stable perovskite solar cells are discussed.

关键词： Perovskite solar cell Additive Solar modules Film quality

Altered histone retention and epigenetic modifications in the sperm of infertile men

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Asian Journal of Andrology 2012年第2期14卷 239-240页

作者： Rafael Oliva Josep luis Ballesca Genetics Unit Department of Physiological Sciences I University of Barcelona Biochemistry and Molecular Genetics Service and Andrology Unit Hospital Clinic 08036 Barcelona Spain

It is well know that the nuclei of spermatogenic cells experience one of the most extremely marked chromatin changes known in cells. At the end of spermatogenesis, the histones are removed in many species and the DNA ... 详细信息

关键词： Sustainability Environmental sciences Biogeography Biogeochemistry

Cover Crops as Affecting Soil Chemical and Physical Properties and Development of Upland Rice and Soybean Cultivated in Rotation

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Rice science 2018年第6期25卷 340-349页

作者： Adriano Stephan NASCENTE luis Fernando STONE Embrapa Arroz e Feij(CNPAF) Rodovia GO-462km 12 Zona RuralCP.17975375-000Santo Antoio de GoiasGOBrasil

Cover crops can provide changes in soil chemical and physical properties, which could allow a sustainable development of soybean and upland rice rotation in Brazilian Cerrado. The objective of this study was to determine the effects of cover crops(cultivated in the offseason) in the soybean-upland rice rotation(cultivated in the summer season) on the soil chemical and physical properties, yield components and grain yield of the cash crops. The experimental design was a randomized block design in factorial scheme 4 × 2 with six replications. Treatments were composed by four cover crops: fallow, millet(Pennisetum glaucum) + Crotalaria ochroleuca, millet + pigeon pea(Cajanus cajans), and millet + pigeon pea + Urochola ruziziensis in the offseason with one or two cycles of cover crops, with rice(Oryza sativa)or soybean(Glycine max) in the summer season. Cover crops alone provided no changes in soil chemical properties. However, the rotation cover crops/cash crops/cover crops/cash crops reduced p H, Al and H + Al and increased Ca, Mg, K and Fe contents in the soil. The cover crops millet + pigeon pea and millet + pigeon pea + U. ruziziensis improved soil physical properties in relation to fallow,especially in the 0–0.10 m soil layer. In spite of the improvement of the soil physical properties after two years of rotation with cover crops and cash crops, the soil physical quality was still below the recommended level, showing values of macroporosity, S index and soil aeration capacity lower than 0.10 m3/m3, 0.035 and 0.34, respectively. Upland rice production was higher under mixtures of cover crops than under fallow, mainly because of soil physical changes done by these mixtures of cover *** grain yield was similar under all cover crops tested, but was higher after the rotation cover crops/upland rice/cover crops than after only one cycle of cover crops.

关键词： crop rotation no-tillage system sustainable agriculture tropical agriculture rice soybean

Porous Medium Flow with Both a Fractional Potential Pressure and Fractional Time Derivative

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Chinese Annals of Mathematics,Series B 2017年第1期38卷 45-82页

作者： Mark ALLEN luis CAFFARELLI Alexis VASSEUR Department of Mathematics The University of Texas at AustinAustinTX 78712USA

The authors study a porous medium equation with a right-hand side. The operator has nonlocal diffusion effects given by an inverse fractional Laplacian *** derivative in time is also fractional and is of Caputo-type, which takes into account"memory". The precise model isD_t~αu- div(u(-Δ)^(-σ)u) = f, 0 < σ <1/*** paper poses the problem over {t ∈ R^+, x ∈ R^n} with nonnegative initial data u(0, x) ≥0 as well as the right-hand side f ≥ 0. The existence for weak solutions when f, u(0, x)have exponential decay at infinity is proved. The main result is H¨older continuity for such weak solutions.

关键词： Caputo derivative Marchaud derivative Porous medium equation Hlder continuity Nonlocal diffusion

A Data Security Framework for Cloud Computing Services

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Computer Systems Science & Engineering 2021年第5期37卷 203-218页

作者： luis-Eduardo Bautista-Villalpando Alain Abran Department of Electronic Systems Autonomous University of AguascalientesAguascalientes20131Mexico Department of Software Engineering and Information Technology ETSUniversity of QuebecMontrealH3C 1K3Canada

Cyberattacks are difficult to prevent because the targeted companies and organizations are often relying on new and fundamentally insecure cloudbased technologies,such as the Internet of *** increasing industry adoption and migration of traditional computing services to the cloud,one of the main challenges in cybersecurity is to provide mechanisms to secure these *** work proposes a Data Security Framework for cloud computing services(CCS)that evaluates and improves CCS data security from a software engineering perspective by evaluating the levels of security within the cloud computing paradigm using engineering methods and techniques applied to *** framework is developed by means of a methodology based on a heuristic theory that incorporates knowledge generated by existing works as well as the experience of their *** paper presents the design details of the framework,which consists of three stages:identification of data security requirements,management of data security risks and evaluation of data security performance in CCS.

关键词： Cloud computing services computer security data security data security requirements data risk data security measurement

Evaluation of activity of triclabendazole against Taenia solium metacestode in naturally infected pigs

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Asian Pacific Journal of Tropical Medicine 2016年第1期9卷 20-23页

作者： Ana Vargas-Calla luis A.gomez-Puerta Juan Calcina Omar Gonzales-Viera Cesar Gavidia Maria T.Lopez-Urbina Hector H.Garcia Armando E.Gonzalez School of Veterinary Medicine Universidad Nacional Mayor de San Marcos Cysticercosis Elimination Program and Center for Global Heath Tumbes Universidad Peruana Cayetano Heredia Department of Microbiology School of SciencesUniversidad Peruana Cayetano Heredia

Objective:To assess the efficacy of triclabendazole(TCBZ) in porcine ***:Eighteen naturally infected cysticercotic pigs were divided into 3 groups of 6 individuals *** first group was treated orally with TCBZ at a single dose of 30 mg/kg of body weight,the second group was treated orally with oxfendazole at a single dose of 30 mg/kg of body weight and the third group received a placebo(control group).All animals were kept under the same management *** pigs were euthanized 17 wk post-treatment and the number of surviving cysts in muscles was assessed and compared between ***:All pigs treated with oxfendazole had only degenerated cysts in their *** contrast,TCBZ had very little effect against the parasitic *** from pigs in the TCBZ group looked apparently normal after ***,histological evaluation showed a mild to moderate degree of ***:TCBZ is not an efficacious drug against Taenia solium cysticercosis in swine using a single dose.

关键词： Taenia solium Cysticercosis Triclabendazole Oxfendazole Treatment

Use of two-surfactants mixtures to attain specific HLB values for assisted TPH-diesel biodegradation

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Journal of Environmental Sciences 2004年第6期16卷 950-956页

作者： luis G. Torres Neftalí Rojas Rosario Iturbe Instituto de Ingeniería Universidad Nacional Autó noma de México Coordinación de Ingeniería Ambiental Grupo Saneamiento de Suelos y Acuíferos Apartado Postal 70-472 Coyoacán 04510 México D.F. Mexico

In a surfactant assisted biodegradation process, the choice of surfactant(s) is of crucial importance. The question is: does the type of surfactant(i.e. chemical family) affect the biodegradation process at fixed hidrophillic-lypofillic balance(HLB) values? Microcosm assessments were developed using contaminated soil, with around of 5000 mg/kg of hydrocarbons as TPH-diesel. Mixtures of three nonionic surfactants were employed to get a wide range of specific HLB values. Tween20 and Span20 were mixed in the appropriate proportions to get HLB values between 8.6 and 16.7. Tween/Span60 mixtures reached HLB values between 4.7 and 14.9. Finally, Tween/Span80 combinations yielded HLB values between 4.3 and 15. TPH-diesel biodegradation was measured at the beginning, and after 8 weeks, as well as the FCU/gr soil, as a measure of microorganisms′ development during the biodegradation period. A second aim of this work was to assess the use of guar gum as a biodegradation enhancer instead of synthetic products. The conclusions of this work are that surfactant chemical family, and not only the HLB value clearly affects the assisted biodegradation rate. Surfactant's synergism was clearly observed. Regarding the use of guar gum, no biodegradation enhancement was observed for the three assessed concentrations, i.e., 2, 20, and 200 mg/kg, respectively. On the contrary, TPH-diesel removal was lower as the gum concentration increased. It is quite possible that guar gum was used as a microbial substrate.

关键词： aged soils enhanced bioremediation HLB mixtures Tween Span surfactants

Strength and stiffness reduction factors for infilled frames with openings

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Earthquake Engineering and Engineering Vibration 2014年第3期13卷 437-454页

作者： luis D.Decanini Laura Liberatore Fabrizio Mollaioli Department of Structural Engineering and Geothecnics "Sapienza" University of Rome

Framed structures are usually infilled with masonry walls. They may cause a significant increase in both stiffness and strength, reducing the deformation demand and increasing the energy dissipation capacity of the system. On the other hand, irregular arrangements of the masonry panels may lead to the concentration of damage in some regions, with negative effects; for example soft story mechanisms and shear failures in short columns. Therefore, the presence ofinfill walls should not be neglected, especially in regions of moderate and high seismicity. To this aim, simple models are available for solid infills walls, such as the diagonal no-tension strut model, while infilled frames with openings have not been adequately investigated. In this study, the effect of openings on the strength and stiffness of infilled frames is investigated by means of about 150 experimental and numerical tests. The main parameters involved are identified and a simple model to take into account the openings in the infills is developed and compared with other models proposed by different researchers. The model, which is based on the use of strength and stiffness reduction factors, takes into account the opening dimensions and presence of reinforcing elements around the opening. An example of an application of the proposed reduction factors is also presented.

关键词： infilled frames openings strength stiffness reduction factor

Cell bioenergetics:Simple logics,complex solut

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BIOCELL 2022年第10期46卷 2217-2220页

作者： luis S.MAYORGA Instituto de Histología y Embriología de Mendoza(IHEM Universidad Nacional de CuyoCONICET)Facultad de Ciencias Exactas y NaturalesMendoza5500Argentina

Cells are open systems that exchange energy and molecules with their *** any material system,they perform all the complex activities required for homeostasis and reproduction,obeying the thermodynamic *** viewpoint will argue that the basic logic governing the energy flux required to preserve cell organization and function is simple:to decrease the activation energy(Ea)of specific *** none of the possible chemical reactions and energy transformations inside a cell occur at a measurable speed at room or body *** or other macromolecular structures speed up particular transformations by decreasing the corresponding energetic ***,to maintain the systems in a homeostatic state,capable of sophisticated functions based on this simple strategy requires an inconceivably complex *** conclusion will point to the challenging and intricate problems that cells have solved to carve the highly regulated channel through which the energy flows,fueling the work of these nanoscale machines.

关键词： Thermodynamics Cellular logics Self-organization Complexity