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Experimental investigation for temperature and emissivity by flame emission spectrum in a cavity of rocket based combined cycle combustor chamber

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Defence Technology 2024年第09期 114-122页

作者： Weiguang Cai Shu Zheng Yan Wang Bing Liu Shaohua Zhu Li Zhao Qiang Lu National Engineering Research Center of New Energy Power Generation North China Electric Power University Science and Technology on Combustion Internal Flow and Thermal-structure Laboratory Northwestern Polytechnical University

Flame temperature and spectral emissivity were the important parameters characterizing the sufficient degree of fuel combustion and the particle radiative characteristics in the Rocket Based Combined Cycle(RBCC) combustor. To investigate the combustion characteristics of the complex supersonic flame in the RBCC combustor, a new radiation thermometry combined with Levenberg-Marquardt(LM) algorithm and the least squares method was proposed to measure the temperature, emissivity and spectral radiative properties based on the flame emission spectrum. In-situ measurements of the flame temperature,emissivity and spectral radiative properties were carried out in the RBCC direct-connected test bench with laser-induced plasma combustion enhancement(LIPCE) and without LIPCE. The flame average temperatures at fuel global equivalence ratio(a) of 1.0b and 0.6 with LIPCE were 4.51% and 2.08% higher than those without LIPCE. The flame combustion oscillation of kerosene tended to be stable in the recirculation zone of cavity with the thermal and chemical effects of laser induced plasma. The differences of flame temperature at a = 1.0b and 0.6 were 503 K and 523 K with LIPCE, which were 20.07% and42.64% lower than those without LIPCE. The flame emissivity with methane assisted ignition was 80.46%lower than that without methane assisted ignition, due to the carbon-hydrogen ratio of kerosene was higher than that of methane. The spectral emissivities at 600 nm with LIPCE were 1.25%, 22.2%, and 4.22%lower than those without LIPCE at a = 1.0a(with methane assisted ignition), 1.0b(without methane assisted ignition) and 0.6. The effect of concentration in the emissivity was removed by normalization to analyze the flame radiative properties in the RBCC combustor chamber. The maximum differences of flame normalized emissivity were 50.91% without LIPCE and 27.53% with LIPCE. The flame radiative properties were stabilized under the thermal and chemical effects of laser induced plasma at a = 0.

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Beta-lactam antibiotic resistance among Escherichia coli isolates from patients with urinary tract infections in Vietnam:A systematic review and meta-analysis

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Asian Pacific Journal of Tropical Medicine 2024年第6期17卷 243-255,I0001-I0003页

作者： Dat T Nguyen Princess Margaret Cancer centre University Health NetworkTorontoOntarioCanada

Objective:To investigate the evolving patterns of antimicrobial resistance against beta-lactam antibiotics in Escherichia coli isolates from urinary tract infection patients in Vietnam,covering the period from 2005 to ***:29 Descriptive studies published between 2010 and 2022 in English and Vietnamese were included in the *** on resistance rates to beta-lactam antibiotics,including cephalosporins and carbapenems,were extracted and *** pooled resistance rates were calculated using random-effects *** trends in resistance were assessed using linear regression ***:Among the beta-lactam antibiotics studied,Escherichia coli exhibited varying levels of resistance,with cephalosporins showing higher resistance rates compared to *** pooled resistance rates were 66%for cefotaxime,65%for ceftriaxone,54%for ceftazidime,and 56%for *** contrast,carbapenems demonstrated lower resistance rates,with weighted pooled resistance rates ranging from 3%to 4%for meropenem,ertapenem,and *** rates were also observed for amoxicillin/clavulanate(35%),ticarcillin/clavulanate(26%),and piperacillin/tazobactam(12%).Significant annual increases in resistance were noted for imipenem(0.56%,P<0.001).Conclusions:This study highlights the critical issue of antimicrobial resistance in urinary tract infections in Vietnam and emphasizes the importance of prudent antibiotic use and the regular monitoring of resistance *** insights are useful for guiding healthcare professionals in optimizing treatment strategies and for policymakers in formulating evidence-based clinical guidelines to combat antibiotic resistance effectively.

关键词： Antimicrobial resistance Urinary tract infection Vietnam

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Morphological and molecular description of a new species of sandfly,Sergentomyia(Neophlebotomus)ashwanii ***.(Diptera:Psychodidae)from Western Ghats,India

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Asian Pacific Journal of Tropical Medicine 2024年第5期17卷 226-234页

作者： Prasanta Saini Harish Kumar Shah Mathew Jessu Sonia T Tom Anns KP Amju ICMR-Vector Control Research centre(Field Station) KottayamKeralaIndia

Objective:To report a new species of sandfly,Sergentomyia(Neophlebotomus)ashwanii ***.(Diptera:Psychodidae)from Western Ghats,***:A systematic sandfly survey was conducted in the Thrissur and Kollam districts of Kerala,India using mechanical aspirators,light and sticky traps,both indoor and outdoor habitats,for a period of one *** acid barcoding of samples was performed targeting mitochondrial cytochrome oxidase I(COI)gene and sequence generated was subjected to phylogenetic ***:Sergentomyia(Neophlebotomus)ashwanii,a new sandfly species is recorded and described in this communication.A single row of 10-12 pointed teeth in the cibarium with 4-6 small denticles or fore-teeth are the key characteristics that is distinctive from other members of the subgenus *** COI barcode followed by phylogenetic analysis of the nucleotide sequence confirms that specimens of the species belong to the same taxonomic group while the genetic distance(14.2%)with the congeners established it to be a different ***:The Western Ghats'being an important biodiversity hotspot and has dearth of systematic entomological surveys on *** current study tried to fill the void and also report a new sandfly species.

关键词： Sergentomyia(Neophlebotomus)ashwanii COI barcode Western Ghats Phlebotomine sandflies

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Quantum dense coding with gravitational cat states

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Communications in Theoretical Physics 2024年第3期76卷 84-90页

作者： Saeed Haddadi Mehrdad Ghominejad Artur Czerwinski Faculty of Physics Semnan UniversityP.O.Box 35195-363SemnanIran centre for Quantum Optical Technologies Centre of New TechnologiesUniversity of WarsawBanacha 2c02-097 WarszawaPoland

A protocol of quantum dense coding with gravitational cat states is *** explore the effects of temperature and system parameters on dense coding capacity and provide an efficient strategy to preserve the quantum advantage of dense coding for these *** results may open new opportunities for secure communication and insights into the fundamental nature of gravity in the context of quantum information processing.

关键词： quantum dense coding gravitational cat states quantum advantage

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CAOSA-extracted lignin improves enzymatic hydrolysis of cellulose

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Green Energy & Environment 2024年第7期9卷 1101-1111页

作者： Sen Ma Zheng Li Jonathan Sperry Xing Tang Yong Sun Lu Lin Jian Liu Xianhai Zeng College of Energy State Key Laboratory of Physical Chemistry of Solid Surfaces Xiamen University Fujian Engineering and Research centre of Clean and High-valued Technologies for Biomass Xiamen Key Laboratory of Clean and High-valued Utilization of Biomass centre for Green Chemical Science University of Auckland

The conversion of biomass into sugar platform compounds is very important for the biorefinery industry. Pretreatment is essential to the biomass of the sugar platform, however, the lignin obtained by pretreatment, as a key part of lignocellulose, generally has a passive effect on the enzymatic hydrolysis of cellulose into sugars. In this study, p-TsOH(p-toluenesulfonic acid), DES(Deep eutectic solvent) and CAOSA(cooking with active oxygen and solid alkali) pretreatment ways were used to fraction lignin from bamboo biomass. After CAOSA treatment, the hydrolysis efficiency of the pulp was 95.57%. Moreover, the effect of different treatment methods on lignin properties was studied and the promotion effect of lignin was investigated by adding it to the cellulose enzymatic hydrolysis system. In this work, the results showed that CAOSA-extracted lignin with lower ?(1.31–1.25) had a better adsorption effect on the enzyme protein. p-TsOH-extracted lignin with a larger S/G ratio enhanced the inhibition of enzymatic hydrolysis. In addition, the presence of-COOHs in lignin could reduce its inhibitory effect on cellulose saccharification.

关键词： Biomass pretreatment CAOSA Cellulose hydrolysis Lignin Enzyme

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EVOLUTION AND INTERACTION OFδ-WAVES IN THE ZERO-PRESSURE GAS DYNAMICS SYSTEM

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Acta Mathematica Scientia 2024年第5期44卷 1801-1836页

作者： Abhishek DAS K.T.JOSEPH centre for Data Science Institute of Technical Education and Research(ITER)Siksha‘O’Anusandhan(Deemed to be University)BhubaneswarOdisha751030India centre for Applicable Mathematics Tata Institute of Fundamental ResearchSharada NagarBangalore560065KarnatakaIndia

Evolution and interaction of plane waves of the multidimensional zero-pressure gas dynamics system leads to the study of the corresponding one dimensional *** this paper,we study the initial value problem for one dimensional zero-pressure gas dynamics *** the first equation is the Burgers equation and the second one is the continuity *** consider the solution with initial data in the space of bounded Borel *** we prove a general existence result in the algebra of generalized functions of *** we study in detail special solutions withδ-measures as initial *** study interaction of waves originating from initial data concentrated on two point sources and interaction with classical shock/rarefaction *** gives an understanding of plane-wave interactions in the multidimensional *** use the vanishing viscosity method in our analysis as this gives the physical solution.

关键词： zero-pressure gas dynamics delta-waves interaction of waves

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Redefining biofuels:Investigating oil palm biomass as a promising cellulose feedstock for nitrocellulose-based propellant production

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Defence Technology（防务技术） 2024年第7期37卷 111-132页

作者： Khoirul Solehah binti Abdul Rahim Alinda binti Samsuri Siti Hasnawati binti Jamal Siti Aminah binti Mohd Nor Siti Nor Ain binti Rusly Hafizah binti Ariff Nur Shazwani binti Abdul Latif centre for Tropicalization(CENTROP) Defence Research InstituteUniversiti Pertahanan Nasional MalaysiaKem Sungai Besi57000 Kuala LumpurMalaysia Department of Chemistry and Biology Centre for Defence Foundation StudiesUniversiti Pertahanan Nasional MalaysiaKem Sungai Besi57000 Kuala LumpurMalaysia

This review paper explores the potential of oil palm biomass as a valuable cellulose source for the production of nitrocellulose-based propellants,contributing to the green revolution and sustainable energy *** highlights the availability of the corresponding biomass in Malaysia and in line with global studies,the chemical compositions,as well as a brief description of current technologies for converting biomass of oil palm into value added products specifically *** to achieve maximum utilization of biomass from oil palm industry for cellulose production and prospective source for nitrocellulose-based propellant are also *** methodology section outlines the pretreatment of lignocellulosic fibres,cellulose extraction,and nitrocellulose production ***,the review underscores the prospective of palm oil biomass as a sustainable cellulose source for propellant manufacturing,while acknowledging the need for further research and advancements in the field.

关键词： Biopolymer Cellulose nitrate Energetic materials Green technology Palm oil

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Magnetic and electronic properties of La-doped hexagonal 4H-SrMnO3

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Chinese Physics B 2024年第1期33卷 725-729页

作者：李杰陈一楠宫诺黄欣杨志红翁亚奎 Grünberg Research centre Nanjing University of Posts and Telecommunications School of Science Nanjing University of Posts and Telecommunications

As typical strongly correlated electronic materials, manganites show rich magnetic phase diagrams and electronic structures depending on the doped carrier density. Most previous relevant studies of doped manganites rely on the cubic/orthorhombic structures, while the hexagonal structure is much less studied. Here first-principles calculations are employed to investigate the magnetic and electronic structures of La-doped 4H-SrMnO3. By systematically analyzing the two kinds of La-doped positions, our calculations predict that the doped electron with lattice distortion would prefer to form polarons, which contribute to the local magnetic phase transition, nonzero net magnetization, and semiconducting behavior. In addition, the energy gap decreases gradually with increasing doping concentration, indicating a tendency of insulator–metal transition.

关键词： manganites polaron magnetic phase transition

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FAST unveils a new era in the discovery of long-period pulsars in globular clusters

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Science China(Physics,Mechanics & Astronomy) 2024年第6期67卷 185-186页

作者： Zhanwen Han International centre of Supernovae Yunnan Key LaboratoryYunnan ObservatoriesChinese Academy of SciencesKunming 650011China

Globular clusters(GC)are among the oldest celestial bodies in the Milky *** possessing millions of stars and have been going through abundant stellar interactions,GCs are futile ground for hunting for compact objects,particularly,neutron stars.A significant number of fast-spinning millisecond pulsars(MSPs)have been discovered,comprising the majority of known GC pulsars.

关键词： stars pulsars abundant

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Evaluation of soil loss severity and ecological restoration approach for sustainable agriculture in the Hindu Kush, Karakoram and Himalaya region

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Journal of Mountain Science 2024年第5期21卷 1509-1521页

作者： Arshad ASHRAF Imran AHMAD Climate Energy and Water Research InstituteNational Agricultural Research Centre(NARC)Islamabad 44000Pakistan

Soil erosion has resulted in removal of the topsoils containing fine soil particles and plant nutrients, causing decrease in soil fertility in the Hindu Kush, Karakoram and Himalaya(HKH) region. The existing production of cereal crop grains has been reduced to one third of the potential crop grains production owing to land degradation and poor farming practices. It is necessary to assess risk of soil loss and identify appropriate controlling measures to address issues of low agriculture productivity and water insecurity in the region. In the present study, severity of soil loss was predicted using Revised Universal Loss Equation(RUSLE) and ecological measures were identified for sustainable mountain agriculture in the HKH region of Upper Indus Basin, Pakistan. Overall 62.6% area was found to have very low risk of soil loss, i.e., 100 t/(ha·yr) in about 6.8% and 7.4% areas respectively. The mean rate of soil loss was about 41.9 t/(ha·yr) in the Hindu Kush, 31.1 t/(ha·yr) in the Himalayas, 18.8 t/(ha·yr) in the Karakoram and overall 29.7 t/(ha·yr) in the three HKH ranges. As such no considerable measures have been adopted by the communities for restoration of the degraded areas except raising fruit/farm trees and supporting limited social forestry for their livelihoods. The slopes cleared for cultivation and susceptible to erosion may be stabilized through sowing/planting of multi-purpose plant species and formation of proper bench terraces. The conservation of forest ecosystem and pastures at higher elevations would help in reducing overland water flow, risk of flash flood hazard and minimizing sediment loads in the downstream. It is essential to adopt site-specific resource conservation techniques and restore possible ecosystem health for sustainable agriculture and economic developm

关键词： Climate change Erodibility Indus basin Land degradation Slope stabilization

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