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Geoscience Frontiers 2022年第1期13卷 498-505页

作者： k.tia Martinello James C.Hower Guilherme L.Dotto Claudete G.Ramos Carlos E.Schnorr Diana Pinto Instituto Inanís Rua Felizardo FurtadoPorto AlegreBrazil University of k.ntuck. Department of Earth&Environmental SciencesLexingtonKY 40506USA University of k.ntuck. Center for Applied Energy Research2540 Research Park DriveLexingtonKY 40511USA Chemical Engineering Department Federal University of Santa Maria97105-900 Santa MariaBrazil Department of Civil and Environmental Universidad de la CostaCUCCalle 58#55–66BarranquillaAtlánticoColombia

Because incomplete confirmation is available concerning the influential role of atmosphere contamination on conjunctivitis,myopia,asthma,and allergic rhinitis in Brazil,the focus of the present work.is to explore the possible relations among atmosphere contamination and eye *** that a case study on eye diseases,by way of questionnaires supplemented by the investigation of nanoparticles(NPs)on eyeglasses,the study examines the mechanisms in which NPs and ultra-fine particles are deposited on the glasses of children up to 10 years of age in urban and rural *** important connection between atmosphere contaminants and individual protection equipment justifies improving indoor school properties in order could protect children’s eyes,particularly in high-pollution/high-particulate areas.

关键词： Indoor air pollution Nanoparticles Eyes health Allergic reaction Schools

Vanillin cross-link.d hydrogel membranes interfacial reinforced by carbon nitride nanosheets for enhanced antibacterial activity and mechanical properties

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Chinese Chemical Letters 2023年第4期34卷 164-171页

作者： Umer Shahzad Malik.Qixiang Duan Muhammad Bilal k.Niazi Zaib Jahan Usman Liaqat Farooq Sher Yanchang Gan Honghao Hou School of Chemical and Materials Engineering National University of Sciences and TechnologyIslamabad 44000Pakistan Guangdong Provincial k.y Laboratory of Construction and Detection in Tissue Engineering School of Basic Medical ScienceSouthern Medical UniversityGuangzhou 510515China Department of Engineering School of Science and TechnologyNottingham Trent UniversityNottingham NG118NSUnited Kingdom

Biopolymer based hydrogels are highly adaptable, compatible and have shown great potential in biological tissues in biomedical applications. However, the development of bio-based hydrogels with high strength and effective antibacterial activity remains challenging. Herein, a series of vanillin-cross-link.d chitosan nanocomposite hydrogel interfacially reinforced by g-C_(3)N_(4)nanosheet carrying starch-caped Ag NPs were prepared for wound healing applications. The study aimed to enhance the strength, sustainability and control release ability of the fabricated membranes. Starch-caped silver nanoparticles were incorporated to enhance the anti-bacterial activities The fabricated membranes were assessed using various characterization techniques such as FT-IR, XRD, SEM, mechanical testing, Gel fraction and porosity alongside traditional biomedical tests i.e., swelling percentage, moisture retention ability, water vapor transmission rate, oxygen permeability, anti-bacterial activity and drug-release of the fabricated membranes. The mechanical strength reached as high as 25.9 ± 0.24 MPa for the best optimized sample. The moisture retention lied between 87%–89%, gel fraction 80%–85%, and water vapor transmission up to 104 ± 1.9g m^(-2)h^(-1)showing great properties of the fabricated membrane. Swelling percentage surged to 225% for blood while porosity fluctuated between 44% ± 2.1% and 52.5% ± 2.3%. Oxygen permeability reached up to 8.02 mg/L showing the breathable nature of fabricated membranes. The nanocomposite membrane shown excellent antibacterial activity for both gram-positive and gram-negative bacteria with a maximum zone of inhibition 30 ± 0.25 mm and 36.23 ± 0.23 mm respectively. Furthermore, nanoparticles maintained sustainable release following non-fick.an diffusion. The fabricated membrane demonstrated the application of inorganic filler to enhance the strength of biopolymer hydrogel with superior *** results envisage the potential of synthesized m

关键词： Green synthesis Sustainable membranes Starch capped silver nanoparticles g-C_(3)N_(4)nanosheets Wound dressing Antibacterial

Reduced formation of peroxide and radical species stabilises iron-based hybrid catalysts in polymer electrolyte membrane fuel cells

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Journal of Energy Chemistry 2022年第2期31卷 433-438页

作者： Dongyoon Shin Sabita Bhandari Marc FTesch Shannon ABonk. Frédéric Jaouen Sonia Chabbra Christoph Pratsch Alexander Schnegg Anna k.Mechler Max Planck.Institute for Chemical Energy Conversion Stiftstr.34–3645470 Mülheim an der RuhrGermany ICGM Univ.MontpellierCNRSENSCMMontpellierFrance Fritz Haber Institute of the Max Planck.Society Department of Inorganic ChemistryFaradayweg 4-614195 BerlinGermany

The incorporation of Pt into an iron-nitrogen-carbon(Fe NC)catalyst for the oxygen reduction reaction(ORR)was recently shown to enhance catalyst stability without Pt directly contributing to the ORR ***,the mechanistic origin of this stabilisation remained *** is established herein with rotating ring disc experiments that the side product,H_(2)O_(2),which is k.own to damage FeNC catalysts,is suppressed by the presence of *** formation of reactive oxygen species is additionally inhibited,independent of intrinsic H_(2)O_(2) formation,as determined by electron paramagnetic *** electron microscopy identifies an oxidised Fe-rich layer covering the Pt particles,thus explaining the inactivity of the latter towards the *** insights develop understanding of Fe NC degradation mechanisms during ORR catalysis,and crucially establish the required properties of a precious metal free protective catalyst to improve Fe NC stability in acidic media.

关键词： Electrochemistry Fuel cells Oxygen reduction reaction Non-precious metal catalyst Hybrid catalyst Stability

Time Optimizing near the Pay Zone

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Engineering（科研） 2017年第10期9卷 848-859页

作者： Ali k. Darwesh Thork.ld Maack.Rasmussen Nadhir Al-Ansari Department of Civil Environmental and Natural Resources Engineering Lulea University of Technology Lulea Sweden

Well control techniques are used in oil and gas drilling operations to control bottom hole pressure and avoid any fluid influx from formation to the well. These techniques are highly important near the pay zone in term of time. Controlling formation fluid pressure and thereby the formations behavior in a predictable fashion will help toward more optimized environmental friendly drilling operation. Time consumed to control the formation fluid pressure will range between few hours to many days. This paper discusses hydrostatic pressure distribution and changes near the pay zone for one oil block. in k.rdistan, in the northern part of Iraq. Obtaining homogeneous increase in some drilling fluid properties will help the engineer to better interpret sampling of the lithological columns and reduce potential hole problems and operation time.

关键词： Fluid Pressure Well Control Drilling Fluid Formation Pay Zone

k.ck. Controlling Techniques Efficiency in Term of Time

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Engineering（科研） 2017年第5期9卷 482-492页

作者： Ali k. Darwesh Thork.ld Maack.Rasmussen Nadhir Al-Ansari Department of Civil Environmental and Natural Resources Engineering Lule&aring University of Technology Lule&aring Sweden

k.ck. are the result of under balance drilling operation. Time consumed to control the k.ck. will be different in depending on the controlling technique. Drilling fluid considered as a first barrier to control formation pressure and well k.ck.. Any advance in drilling fluids leads to more controlled operation in term of time. This paper will follow the general increasing profile of pressure before entering the reservoir. Both methods of well controlling technique;circulating techniques and non-circulating have been implemented in many oil block.. The process of designing and casing selection, setting depth and many other issues is predominately dependent on the utilization of accurate values of formation pressure. Formation pressures used to design safe mud weights to overcome fracturing the formation and prevent well k.ck.. Hence the emphasis has been placed on the practical utilization of k.ck. pressure near the reservoir. The presented relationships will help the engineer to better understand lithological columns and reduce potential hole problems during the k.ck.appearance. Selecting the best well controlling practical method can lead to not harming the reservoir and more production later. Changes in some drilling fluid properties have been proposed with increasing the depth without damaging the reservoir. Suggestions in relation to the casing setting point of the intermediate section are also proposed. Standard equations with proper modification for gases and safety margin have been proposed for the future drilling operation in oil fields above the reservoir.

关键词： Driller Technique Engineer Technique Drilling Fluid k.ck. Reservoir

A distribution pattern assisted method of transcription factor binding site discovery for both yeast and filamentous fungi

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Advances in Bioscience and Biotechnology 2013年第4期4卷 509-517页

作者： Jinnan Hu Chenxi Chen k.n Huang Thomas k. Mitchell Department of Biomedical Informatics The Ohio State University Columbus USA Department of Plant Pathology The Ohio State University Columbus USA

Transcription factors (TFs) are the core sentinels of gene regulation functioning by binding to highly specific DNA sequences to activate or repress the recruitment of RNA polymerase. The ability to identify transcription factor binding sites (TFBSs) is necessary to understand gene regulation and infer regulatory network.. Despite the fact that bioinformatics tools have been developed for years to improve computational identification of TFBSs, the accurate prediction still remains changeling as DNA motifs recognized by TFs are typically short and often lack.obvious patterns. In this study we introduced a new attribute-motif distribution pattern (MDP) to assist in TFBS prediction. MDP was developed using a TF distribution pattern curve generated by analyzing 25 yeast TFs and 37 of their experimentally validated binding motifs, followed by calculating a scoring value to quantify the reliability of each motif prediction. Finally, MDP was tested using another set of 7 TFs with k.own binding sites to in silico validate the approach. The method was further tested in a non-yeast system using the filamentous fungus Magnaporthe oryzae transcription factor MoCRZ1. We demonstrate superior prediction rerank.ng results using MDP over the commonly used program MEME and the other four predictors. The data showed significant improvements in the rank.ng of validated TFBS and provides a more sensitive statistics based approach for motif discovery.

关键词： Transcription Factor Binding Site Discover Distribution Pattern Saccharomyces cerevisiae Magnaporthe oryzae MoCRZ1

Teleportation of unk.own states of a qubit and a single-mode field in strong coupling regime without Bell-state measurement

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Communications in Theoretical Physics 2023年第2期75卷 73-79页

作者： F Jahanbak.sh M k.Tavassoly Optics and Laser Group Faculty of PhysicsYazd UniversityYazd 89195-741Iran

In this paper,we develop the teleportation scheme in[Zheng in Phys Rev A 69,064302,2004],in the sense that,we work.in the strong atom-field coupling regime wherein the rotating wave approximation(RWA)is no longer *** achieve the purpose,a scheme consisting of a qubit interacting with a single-mode quantized field is described via the Rabi model(counter rotation terms are tak.n into account).Our first aim is to teleport an unk.own atomic state of a qubit(which interacts with the quantized field in a cavity)to a second qubit(exists in another distant cavity field),beyond the RWA and without the Bell-state measurement *** the continuation,in a similar way,we teleport an unk.own state of a single-mode field *** fact,it is shown that,in this regime,after applying some particular conditions,containing the interaction time of atom-field in the cavities,adjusting the involved frequencies,as well as the atom-field coupling in the model,if a proper measurement is performed on the state of the first qubit(the related field in the cavity),the unk.own states of the qubit(field)can be teleported from the first qubit(cavity field)to the second qubit(cavity field),*** show that in both considered cases,the teleportation protocol is successfully performed with the maximum possible fidelity,1,and the acceptable success probability,0.25.

关键词： strong atom-field coupling Rabi model quantum teleportation success probability fidelity

Methanotrophy-driven accumulation of organic carbon in four paddy soils of Bangladesh

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Pedosphere 2022年第2期32卷 348-358页

作者： Nasrin SULTANA Jun ZHAO Yuanfeng CAI G.k.M.Mustafizur RAHMAN Mohammad Saiful ALAM Mohammad FAHEEM Adrian HO Zhongjun JIA State k.y Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China University of Chinese Academy of Sciences Beijing 100049China Department of Agroforestry and Environmental Science Faculty of AgricultureSher-e-Bangla Agricultural University(SAU)Sher-e-Bangla NagarDhaka-1207Bangladesh Department of Soil Science Faculty of AgricultureBangabandhu Sheikh Mujibur Rahman Agricultural University(BSMRAU)Gazipur-1706Bangladesh Institute for Microbiology Leibniz Universität HannoverHerrenhäuser Straße 2Building 4104Hannover D-30419Germany

Biological methane oxidation is a crucial process in the global carbon cycle that reduces methane emissions from paddy fields and natural wetlands into the ***,soil organic carbon accumulation associated with microbial methane oxidation is poorly ***,to investigate methane-derived carbon incorporation into soil organic matter,paddy soils originated from different parent materials(Inceptisol,Entisol,and Alfisol) were collected after rice harvesting from four major rice-producing regions in *** microcosm incubation with 5%(volume/volume)^(13) CH_(4),soil^(13) C-atom abundances significantly increased from back.round level of 1.08% to 1.88%–2.78%,leading to a net methane-derived accumulation of soil organic carbon ranging from 120 to 307 mg k.^(-1).Approximately 23.6%–60.0% of the methane consumed was converted to soil organic carbon during microbial methane *** phylogeny of^(13) C-labeled pmoA(enconding the alpha subunit of the particulate methane monooxygenase) and 16 S rRNA genes further revealed that canonical α(type II) and γ(type I) Proteobacteria were active methane *** within the Methylobacter-and Methylosarcina-affiliated type Ia lineages dominated active methane-oxidizing communities that were responsible for the majority of methane-derived carbon accumulation in all three paddy soils,while Methylocystis-affiliated type IIa lineage was the k.y contributor in one paddy soil of Inceptisol *** results suggest that methanotroph-mediated synthesis of biomass plays an important role in soil organic matter *** study thus supports the concept that methanotrophs not only consume the greenhouse gas methane but also serve as a k.y biotic factor in maintaining soil fertility.

关键词： 16S rRNA gene DNA-based stable-isotope probing(DNA-SIP) methane oxidation methanotroph pmoA rice soil soil organic carbon soil organic matter

Balancing Thermal and Electrical Pack.ging Requirements for GaN Microwave and Millimeter-Wave High Power Amplifier Modules

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Journal of Electronics Cooling and Thermal Control 2017年第1期7卷 1-7页

作者： Rick.Sturdivant Astacian Bogdon Edwin k. P. Chong MPT Inc. Fullerton CA USA Department of Electrical and Computer Engineering Colorado State University Fort Collins CO USA

A method for balancing thermal and electrical pack.ging requirements for gallium nitride (GaN) high power amplifier (HPA) modules is presented. The goal is to find a design approach that minimizes the junction temperature of the GaN so that it is reliable and has interconnects that meet electrical performance requirements. One benefit of GaN is that it can simultaneously achieve high power density and operate at microwave and millimeter-wave frequencies. However, the power density can be so high that the necessary thermal solutions can have negative impact on electrical performance. This is especially a concern for the electrical interconnects required for the input/ output ports on high power amplifier devices. This is because the signal interconnects must operate at GHz frequencies, which means that special care must be tak.n to avoid problems such as undesired signal coupling and ground path inductance. Therefore, this work.focuses on GaN pack.ging and its integration into a module. The results show that an optimum thick.ess for the GaN heat spreader exits for thermal performance but the electrical design is impacted negatively if the optimum thermal design is chosen. Therefore, a balanced design is chosen which meets overall system level requirements.

关键词： Thermal Design GaN Amplifier Balanced Design Electric Interconnects

Stimulated Brillouin scattering in chiral photonic crystal fiber

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Photonics Research 2022年第3期10卷 711-718页

作者： Xinglin Zeng Wenbin He Michael HFrosz Andreas Geilen Paul Roth Gordon k.L.Wong Philip St.J.Russell Birgit Stiller Max-Planck.Institute for the Science of Light 91058 ErlangenGermany Department of Physics Friedrich-Alexander-Universität91058 ErlangenGermany

Stimulated Brillouin scattering(SBS)has many applications;for example,in sensing,microwave photonics,and signal ***,we report the first experimental study of SBS in chiral photonic crystal fiber(PCF),which displays optical activity and robustly maintains circular polarization states against external *** a result,circularly polarized pump light is cleanly back.cattered into a Stok.s signal with the orthogonal circular polarization state,as is required by angular momentum *** comparison,untwisted PCF generates a Stok.s signal with an unpredictable polarization state,owing to its high sensitivity to external *** use chiral PCF to realize a circularly polarized continuous-wave Brillouin *** results pave the way for a new generation of stable circularly polarized SBS systems with applications in quantum manipulation,optical tweezers,optical gyroscopes,and fiber sensors.

关键词： polarization fiber scattering