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Aromatic alcohols oxidation and hydrogen evolution over π-electron conjugated porous carbon nitride rods

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Nano Research 2022年第12期15卷 10148-10157页

作者： Jiawei Xia Neeta Karjule gabriel Mark Michael Volokh Haiqun Chen Menny Shalom Key Laboratory of Advanced Catalytic Materials and Technology Advanced Catalysis and Green Manufacturing Collaborative Innovation CenterChangzhou UniversityChangzhou213164China Department of Chemistry and Ilse Katz Institute for Nanoscale Science and Technology Ben-Gurion University of the NegevBeer-Sheva8410501Israel

Photocatalysis using polymeric carbon nitride(CN)materials is a constantly evolving field,where the variation of synthetic procedures allows the constant improvement of activity by tackling the intrinsic limitations of these materials(optical absorbance,specific surface area,charge migration,etc.).Amongst the possible photocatalytic reactions,the most popular application of CNs is the hydrogen evolution reaction(HER)from *** this work,we design precisely-controlled carbon-doped porous CN rods with extended π-electron conjugation from supramolecular assemblies of melem and co-monomers,which partially substitute nitrogen for carbon atoms at the pyrimidine ring of the *** hydrogen bonds and good thermal stability of the melem-based supramolecular framework allow synthesizing a more ordered structure for improved charge migration;the control from the molecular level over the position of carbon-substituted nitrogen positions tailors the band alignment and photogenerated charge *** optimal photocatalyst shows an excellent HER rate(up to 10.16 mmol·h-1·g-1 under 100 W white light-emitting diode(LED)irradiation,with an apparent quantum efficiency of 20.0%at 405 nm,which is 23.2 times higher compared to a reference bulk CN).To fully harness the benefits of the developed metal-free CNs,selective oxidation reaction of aromatic alcohols is demonstrated with high conversion and selectivity.

关键词： supramolecular assembly π-electron conjugation carbon nitride photocatalytic hydrogen evolution reaction selective aromatic alcohol oxidation

Mixing time in stirred vessels: A review of experimental techniques

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Chinese Journal of Chemical Engineering 2015年第7期23卷 1065-1076页

作者： gabriel Ascanio Center of Applied Sciences and Technological Development National Autonomous University of Mexico Circuito ExteriorCiudad Universitaria

Mixing time is de fined as the time required for achieving a certain degree of homogeneity of injected tracer in a unit operation vessel. It has been used as a key parameter for assessing the performance of a mixing system. From an experimental standpoint, several techniques have been developed for measuring the mixing time. Based on the disturbances to fl ow, they can be classi fied into two groups: non-intrusive and intrusive. However, depending on the type of data generated, they can be also classi fied into direct measurements and indirect measurements(Eulerian and Lagrangian). Since the techniques available for measuring mixing times in an agitated tank do not provide the same information, its choice depends on several factors, namely: accuracy, reproducibility,suitability, cost, sampling speed, type of data, and processing time. A review of the experimental techniques reported in the literature in the last 50 years for the measurement of mixing time in stirred vessels under single and gas–liquid fl ow conditions with Newtonian and non-Newtonian fl uids in the laminar and turbulent regime is made, and a comparison between these techniques is also presented.

关键词： Mixing timeStirred vesselHomogeneity

Innovating for Health in China’s Greater Bay Area

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China CDC weekly 2022年第1期4卷 1-3页

作者： Feichau Pang Puihong Chung gabriel M Leung School of Public Health LKS Faculty of MedicineThe University of Hong KongHong KongChina

The Success of World Metropolitan and Bay Areas The Tokyo Bay Area,the New York Metropolitan Area,and the San Francisco Bay Area are leading regions for science and *** share an economic transformation from industrial or manufacturing bases to predominantly service-based economies with this sector contributing 75%of their gross domestic product(GDP)in *** companies in these locations accounted for 60%of the revenue of the top 100 global tech companies in 2018(1).The success of these locations stems from the convergence of academia,technology giants,government support,and a high density of investors,as well as innovative entrepreneurs(2).

关键词： companies revenue bases

Existence of Weakly Efficient Solutions in Vector Optimization

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Acta Mathematica Sinica,English Series 2008年第4期24卷 599-606页

作者： Lucelina BATISTA SANTOS Marko ROJAS-MEDAR gabriel RUIZ-GARZóN Departamento de Matemática Universidade Federal do Paraná.CP.019081CEP:81531990Curitiba-PRBrazil Universidad del Bío-Bío Facultad de Ciencias Departamento de Ciencias BásicasCampus Fernando MayCasilla 447ChillánChile Departamento de Estadística e I.O. Universidad de CádizE.U.E.EmpresarialesPor-vera 5411403 Jerez de la FronteraSpain

In this paper, we present an existence result for weak efficient solution for the vector optimization problem. The result is stated for invex strongly compactly Lipschitz functions.

关键词： vector optimization weak efficiency generalized convexity Clarke generalized gradient

Major Elements in Lake Muhazi,Rwanda,East Africa

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Acta Geologica Sinica(English Edition) 2009年第5期83卷 927-931页

作者： Jean de la Paix MUPENZI GE Jiwen gabriel HABIYAREMYE China University of Geosciences Institute of Ecology and Environmental Sciences Wuhan 430074 China Hubei Wetland Evolution and Ecological Restoration Key Laboratory Wuhan 430074 China

The aim of this study undertaken at Lake Muhazi in Rwanda was to determine and analyze the major elements present in water. The presence of many major elements （Al, As, Ba, C, Ca, Cu, Fe, H^＋, K, Mg, Mn, N, P, S, Si, and Zn） was determined by spectroscopic technique. The concentrations of the elements were measured in water samples taken from three different locations of the lake from May to August 2008. The lake is polluted by water flow from mountain sides surrounding the lake. Other causes of pollution could be the use of agrochemicals in the sugar land, which surrounds the lake, and human activities near the lake. Finally, we proposed the strategies that can be applied in order to ensure good conservation of the environment and to prevent augmentation of heavy materials into the lake.

关键词： major elements environment spectroscopic technique water pollution Muhazi Lake Rwanda

Analyzing Real-Time Object Detection with YOLO Algorithm in Automotive Applications:A Review

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Computer Modeling in Engineering & Sciences 2024年第12期141卷 1939-1981页

作者： Carmen Gheorghe Mihai Duguleana Razvan gabriel Boboc Cristian Cezar Postelnicu Department of Automotive and Transport Engineering Transilvania University of BrasovBrasov500036Romania

Identifying objects in real-time is a technology that is developing rapidly and has a huge potential for expansion in many technical ***,systems that use image processing to detect objects are based on the information from a single frame.A video camera positioned in the analyzed area captures the image,monitoring in detail the changes that occur between *** You Only Look Once(YOLO)algorithm is a model for detecting objects in images,that is currently known for the accuracy of the data obtained and the fast-working *** study proposes a comprehensive literature review of YOLO research,as well as a bibliometric analysis to map the trends in the automotive field from 2020 to *** detection applications using YOLO were categorized into three primary domains:road traffic,autonomous vehicle development,and industrial settings.A detailed analysis was conducted for each domain,providing quantitative insights into existing *** the various YOLO architectures evaluated(v2–v8,H,X,R,C),YOLO v8 demonstrated superior performance with a mean Average Precision(mAP)of 0.99.

关键词： YOLO automotive autonomous vehicles traffic industry

Parallel LDPC Decoding on GPUs Using a Stream-Based Computing Approach

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Journal of Computer Science & Technology 2009年第5期24卷 913-924页

作者： gabriel Falcao Student Member Shinichi Yamagiwa Vitor Silva Leonel Sousa Senior Member Department of Electrical and Computer Engineering University of Coimbra Instituto de Telecomunicacoes PoloⅡUniversidade de Coimbra 3030-290 Coimbra Portugal INESC-ID Technical University of Lisbon Rua Alves Redol n.9 1000-029 Lisboa Portugal Department of Electrical and Computer Engineering IST Technical University of Lisbon Rua Alves Redol n.9 1000-029 Lisboa Portugal

Low-Density Parity-Check （LDPC） codes are powerful error correcting codes adopted by recent communication standards. LDPC decoders are based on belief propagation algorithms, which make use of a Tanner graph and very intensive message-passing computation, and usually require hardware-based dedicated solutions. With the exponential increase of the computational power of commodity graphics processing units （GPUs）, new opportunities have arisen to develop general purpose processing on GPUs. This paper proposes the use of GPUs for implementing flexible and programmable LDPC decoders. A new stream-based approach is proposed, based on compact data structures to represent the Tanner graph. It is shown that such a challenging application for stream-based computing, because of irregular memory access patterns, memory bandwidth and recursive flow control constraints, can be efficiently implemented on GPUs. The proposal was experimentally evaluated by programming LDPC decoders on GPUs using the Caravela platform, a generic interface tool for managing the kernels＇ execution regardless of the GPU manufacturer and operating system. Moreover, to relatively assess the obtained results, we have also implemented LDPC decoders on general purpose processors with Streaming Single Instruction Multiple Data （SIMD） Extensions. Experimental results show that the solution proposed here efficiently decodes several codewords simultaneously, reducing the processing time by one order of magnitude.

关键词： data-parallel computing graphics processing unit (GPU) Caravela low-density parity-check (LDPC) code error correcting code

Synthesis of2-Oxazolines Using DAST via Beckmann Rearrangement

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Synthesis of2-Oxazolines Using DAST via Beckmann Rearrangeme...

作者： Okello gabriel 东北师范大学

学位级别：硕士

In the recent few decades, discovery of the DAST mediated reaction system for organic reactions to form oxazolines has effected drastic and far-reaching changes in the scientific domain. This invention has engrossed the interest of chemists and is increasing our understanding of how a range of organic synthetic processes are enhanced.-its alluring tendency has been marked by numerous applications such as gasoline （petrol and diesel） and lube oil additives, pharmaceutical industries, surface-active agent, corrosion resistant coating, anti-foaming agents, textile chemicals, adhesives and binders, stabilizers for chlorinated hydrocarbons;thus justifying the rigorous research on the oxazoline compound. Today, extraordinary transformations to various natural products and biologically active molecules have been achieved where various oxazolines are useful as intermediates. Oxazoline intermediates entertain a great diversity of reaction patterns that can stand numerous functional groups. Additionally, oxazoline synthetic protocols using DAST are economically captivating procedures as most procedures have been used as surrogate for the traditionally tedious, toxic and sometimes unreliably low product-yielding. In recent progresses, demonstrations from various researchers make free from ambiguity the contributions of the versatility of modern oxazoline synthesis in the development of pharmaceutical libraries, and also in the polymer, material and petroleum industries. In our special case, methodologies used with other systems are mentioned in passing as a justification as to why oxazolines are considered to be species with special powers. Encouraged by the virtues of this, we have conveniently developed a method for the synthesis of highly functionalized2-oxazolines in a one pot component reaction of Ketoximes using DAST via Beckmann rearrangement. Our choice for using DAST was intended for the development of simple, safe and efficient method for their synthesis of

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Bird habitat preferences drive hemoparasite infection in the Neotropical region

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Integrative Zoology 2021年第5期16卷 755-768页

作者： gabriel Massaccesi DE LA TORRE Karla Magalhães CAMPIÃO Biological Interactions Departamento de ZoologiaUniversidade Federal do ParanáCuritibaBrazil Programa de Pós-graduação em Ecologia e Conservação Universidade Federal do ParanáCuritibaBrazil

The role that the environment plays in vector-borne parasite infection is one of the central factors for understanding disease *** assessed how Neotropical bird foraging strata and habitat preferences determine infection by parasites of the genera Haemoproteus,Plasmodium,Leucocytozoon,and Trypanosoma and filarioids,and tested for phylogenetic signal in these host-parasite *** performed extensive searches of the scientific literature and created a database of hemoparasite *** collected data on host body mass,foraging strata,habitat preference,and migratory status,and tested if host ecological traits predict each hemoparasite occurrence and prevalence using a phylogenetic Bayesian *** of Plasmodium tend to infect birds from tropical forests while birds from altitudinal environments are likely to be infected by species of *** probability of a bird being infected by filarioid or Trypanosoma is higher in lowland *** species that occur in anthropic environments and dry habitats of tropical latitudes are more susceptible to infection by species of *** foraging strata is also influential and bird species that forage in the mid-high and canopy strata are more prone to infection by species of Haemoproteus and *** also identified phylogenetic signal for host-parasite associations with the probability of infection of Neotropical birds by any hemoparasite being more similar among more closely related *** provided a useful framework to identify environments that correlate with hemoparasite infection,which is also helpful for detecting areas with potential suitability for hemoparasite infection due to land conversion and climate change.

关键词： habitat use haemosporidians host-parasite interaction migratory birds prevalence