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TiO_2-modified nano-egg-shell Pd catalyst for selective hydrogenation of acetylene

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Particuology 2010年第3期8卷 251-256页

作者： Jin Gao Qiufeng zhu Lixiong wen Key Lab for Nanomaterials Ministry of Education Beijing University of Chemical Technology Beijing 100029 China Research Center of the Ministry of Education for High Gravity Engineering and Technology Beijing University of Chemical Technology Beijing 100029 China

Pd-based egg-shell nano-catalysts were prepared using porous hollow silica nanoparticles （PHSNs） as support, and the as-prepared catalysts were modified with TiO2 to promote their selectivity for hydro-genation of acetylene. Pd nanoparticles were loaded evenly on PHSNs and TiO2 was loaded on the active Pd particles. The effects of reduction time and temperature and the amount of TiO2 added on catalytic per-formances were investigated by using a fixed-bed micro-reactor. It was found that the catalysts showed better performance when reduced at 300 ℃ than at 500℃, and if reduced for 1 h than 3 h. When the amount of Ti added was 6 times that of Pd, the catalyst showed the highest ethylene selectivity.

关键词： Egg-shell nano-catalyst Porous hollow silica nanoparticles Modification Selective hydrogenation Acetylene

Fabrication of high-pore volume carbon nanosheets with uniform arrangement of mesopores

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Nano Research 2017年第6期10卷 2106-2116页

作者： shuai Wang Fei Cheng Peng Zhang wen-Cui Li An-Hui Lu State Key Laboratory of Fine Chemicals School of Chemical Engineering Dalian University of Technology Dalian 116024 China

Carbon nanosheets with a tunable mesopore size, large pore volume, and good electronic conductivity are synthesized via a solution-chemistry approach. In this synthesis, diaminohexane and graphene oxide （GO） are used as the structural directing agents, and a silica colloid is used as a mesopores template. Diaminohexane plays a crucial role in bridging silica colloid particles and GO, as well as initiating the polymerization of benzoxazine on the surfaces of both the GO and silica, resulting in the formation of a hybrid nanosheet polymer. The carbon nanosheets have graphene embedded in them and have several spherical mesopores with a pore volume up to 3.5 cm^3·g^-1 on their surfaces. These nuerous accessible mesopores in the carbon layers can act as reservoirs to host a high loading of active charge-storage materials with good dispersion and a uniform particle size. Compared with active materials with wide particle-size distributions, the unique proposed configuration with confined and uniform particles exhibits superior electrochemical performance during lithiation and delithiation, espedaUy during long cycles and at high rates.

关键词： mesoporous carbon nanosheet energy storage battery LiFePO4

Succession of Denitrifying Community Composition in Coastal Wetland Soils Along a Salinity Gradient

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Pedosphere 2012年第3期22卷 367-374页

作者： PIAO Zhe ZHANG wen-wen MA shuai LI Yu-Min YIN Shi-Xue Microbiology Section College of Environmental Science and EngineeringYangzhou UniversityYangzhou 225009(China)

To better understand the effect of salinity on denitrification communities, soils along a salinity gradient （ranging from 7.32 to 1.70 mS cm 1） in a wetland along the Yellow Sea coastline in Jiangsu Province, China, were studied using both culture-dependent and -independent methods. Culture efforts yielded 82 isolates in total, 81.7% of which were close relatives of Bacillus sp. based on partial sequences of their 16S rRNA genes. Denaturing gradient gel electrophoresis （DGGE） analysis based on 16S rRNA sequences suggested possible existence of bacterial community succession along the salinity gradient. Clone library analysis based on nosZ gene sequences （coding nitrous oxide reductase） showed that operational taxonomic units （OTUs） associated with α-proteobacteria dominated in all three soils, whereas those associated with β- and γ-subdivisions showed a clear succession. In the high salinity soil, only the OTUs associated with a-subdivision were found. In the medium salinity soil, small proportions of β- （6.5%） and γ-associated （19.6%） OTUs were found. In the low salinity soil, the proportions were further increased to 33% and 25% for β- and γ-Proteobacteria, respectively. Statistic analysis using Unifrac P test showed that nosZ-communities in different saline soils were significantly different from each other. It could be concluded that α-subdivision of nosZ-community tended to be sustained in high salinity environments whereas β and γ-subdivisions, especially the former, tended to be sustained in low salinity environments. Salinity was the key determinant of nosZ-community composition in the environment.

关键词： clone library denaturing gradient gel electrophoresis (DGGE) nosZ gene Yellow Sea coastline

Metasurface array for single-shot spectroscopic ellipsometry

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Light(Science & Applications) 2024年第5期13卷 835-842页

作者： Shun wen Xinyuan Xue shuai Wang Yibo Ni Liqun Sun Yuanmu Yang Department of Precision Instrument State Key Laboratory of Precision Measurement Technology and InstrumentsTsinghua UniversityBeijing 100084China

Spectroscopic ellipsometry is a potent method that is widely adopted for the measurement of thin film thickness and refractive *** conventional ellipsometers utilize mechanically rotating polarizers and grating-based spectrometers for spectropolarimetric ***,we demonstrated a compact metasurface array-based spectroscopic ellipsometry system that allows single-shot spectropolarimetric detection and accurate determination of thin film properties without any mechanical *** silicon-based metasurface array with a highly anisotropic and diverse spectral response is combined with iterative optimization to reconstruct the full Stokes polarization spectrum of the light reflected by the thin film with high ***,the film thickness and refractive index can be determined by fitting the measurement results to a proper material model with high *** approach opens up a new pathway towards a compact and robust spectroscopic ellipsometry system for the high throughput measurement of thin film properties.

关键词： properties. spectroscopic film

CdS/LaFeO_(3) heterojunctions with improved optical properties for visible-light catalytic applications

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Journal of Rare Earths 2024年第5期42卷 879-888,I0003页

作者： Jiaqi Wei wen zhu Xuelian Xu Xiao Xu Junjiang zhu Hubei Key Laboratory of Biomass Fibers and Eco-dyeing&Finishing College of Chemistry and Chemical EngineeringWuhan Textile University ChemistryWuhan430200China

Construction of heterojunctions is a normal and effective strategy to improve the photocatalytic performances of semiconductors,through which both the lifetime and the redox ability of electrons/holes can be improved,as co mpared to the respective *** this basis,we constructed Z-scheme CdS/LaFeO_(3) heterojunctions(CdS/LFO),by in-situ growing different amounts of CdS on the surface of LaFeO_(3),for photocatalytic degradation of tetracycline hydrochloride(TC)in aqueous solution at room *** crystal structure,surface morphology and optoelectronic properties of the COS/LFO heterojunctions were systemically characterized to correlate the reaction *** tests indicate that the CdS/LFO heterojunctions exhibit promising activity for TC degradation under visible light irradiation(λ≥420 nm),with 85%TC conversion obtained at reaction time of 45 min,which is 3.4 and 1.9 times higher than that of CdS and LaFeO_(3).The CdS/LFO heterojunctions are also stable in the reaction and can be reused for four cycles with no appreciable activity *** applicability of CdS/LFO to photocatalytic degradation of organic dyes,as well as the reaction mechanism,was also explored.

关键词： LaFeO_(3) CdS Photocatalytic degradation Tetracycline hydrochloride Reaction mechanism Rare earths

Identification of circRNA/miRNA/mRNA regulatory net-work involving(+)-catechin ameliorates diabetic nephropathy mice

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Food Science and Human Wellness 2022年第3期11卷 660-668页

作者： Chao Chen Dina zhu shuai Zhang wensheng Zhang zhuhai Branch of State Key Laboratory of Earth Surface Processes and Resource Ecology Advanced Institute of Natural SciencesBeijing Normal UniversityZhuhai 519087China Engineering Research Center of Natural Medicine Ministry of EducationAdvanced Insti-tute of Natural SciencesBeijing Normal UniversityZhuhai 519087China International Cooperation Laboratory of Molecular Medicine Academy of Chinese Medical SciencesZhejiang Chinese Medical UniversityHangzhou 310053China Beijing Key Laboratory of Traditional Chinese Medicine Protection and Utilization Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China

(+)-Catechin(CE)is mainly found in green and black tea and has many biological effects,such as antiinflammatory,anti-cancer,anti-viral effects,protecting human organs,especially the *** study aims to identify the circRNAs induced by CE in db/db mice and their roles in diabetic nephropathy *** the db/db mice were treated with CE,RNA-seq was performed to identify the differentially expressed circRNA and *** ceRNA regulatory network was constructed and analyzed using bioinformatics software and public databases(Cytoscape,Clue GO,Mi RWalk,STRING,et al.).Our results revealed that 6 differentially expressed circRNAs are most associated with the cholinergic synapse,neurotrophin signaling pathway,and insulin signaling *** these,circRNA.5549 and circRNA.4712 might regulate Cd36,Cyp26 b1,C8 a,Cyp2 j13,Grem2 genes through ceRNA regulatory mechanism in the presence of CE *** expanded network of proteins interacting with these 5 genes shows that the TGF-βsignaling pathway,signaling pathways regulating pluripotency of stem cell,fat digestion and absorption,and PPAR signaling pathway was highly ***,circRNA.5549 and circRNA.4712 exhibit a promotive function in CE-treated db/db mice,especially in circRNA.5549/miR-29a-5P/Cd36 regulatory network,and this evidence suggest that their ceRNA regulatory network might be a therapeutic target for DN in humans.

关键词： Catechin Diabetic nephropathy CircRNA miRNA ceRNA

Decay rate of Larix gmelinii coarse woody debris on burned patches in the Greater Khingan Mountains

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Journal of Forestry Research 2021年第6期32卷 2349-2363页

作者： Shubo Huang Lixiang wen shuai Yin Meng Guo Fangbing Yu Key Laboratory of Geographical Processes and Ecological Security in Changbai Mountains School of Geographical SciencesNortheast Normal UniversityMinistry of EducationChangchun130024People’s Republic of China Center for Global Environmental Research National Institute for Environmental StudiesTsukuba3058506Japan

The decomposition of coarse woody debris(CWD)affects the energy flow and nutrient cycling in forest *** studies on CWD have focused on the input,decomposition,reserve dynamics,and CWD functions,but coarse woody debris decomposition is complex and the results from different regions vary *** is not clear which factors affect decay rate(k),especially at different decomposition *** this study,a single-exponential decay model was used to analyze the characteristics of CWD decomposition in Larix gmelinii forests over the 33 years following a fire in the Greater Khingan *** results show that the decay rate of coarse woody debris was positively correlated to decay *** average decomposition rate was 0.019,and 41 years and 176 years are needed for a 50%and 95%mass loss,*** nutrient content,density,and water content could explain the variance in the decay rate(~42%)of the decay factors such as amount of leaching,degree of fragmentation,respiration of the debris,and biotransformation,and varied significantly between different decay *** the space-time substitution method,this study arranged the coarse woody debris of different mortality times to form a 33 year chronosequence which revealed the decomposition *** was concluded that the decay rate was mainly explained by structural component of the debris and its nitrogen and water *** paper quantifies the indicators affecting CWD decay to explain the decomposition process.

关键词： Coarse woody debris Decay rate Space–time substitution Boreal forest Fire disturbance

Expression Complementary Disentanglement Network for Facial Expression Recognition

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Chinese Journal of Electronics 2024年第3期33卷 742-752页

作者： Shanmin WANG Hui shuai Lei zhu Qingshan LIU College of Computer Science and Technology Nanjing University of Aeronautics and Astronautics College of Computer and Software Nanjing University of Information Science and Technology School of Information and Control Nanjing University of Information Science and Technology

Disentangling facial expressions from other disturbing facial attributes in face images is an essential topic for facial expression *** methods only care about facial expression disentanglement(FED)itself,ignoring the negative effects of other facial *** to the annotations on limited facial attributes,it is difficult for existing FED solutions to disentangle all disturbance from the input *** solve this issue,we propose an expression complementary disentanglement network(ECDNet).ECDNet proposes to finish the FED task during a face reconstruction process,so as to address all facial attributes during *** from traditional reconstruction models,ECDNet reconstructs face images by progressively generating and combining facial appearance and matching *** designs the expression incentive(EIE) and expression inhibition(EIN) mechanisms,inducing the model to characterize the disentangled expression and complementary parts *** geometry and appearance,generated in the reconstructed process,are dealt with to represent facial expressions and complementary parts,*** combination of distinctive reconstruction model,EIE,and EIN mechanisms ensures the completeness and exactness of the FED *** results on RAF-DB,AffectNet,and CAER-S datasets have proven the effectiveness and superiority of ECDNet.

关键词： Geometry Image recognition Annotations Face recognition Task analysis Image reconstruction Facial features

Characteristics of a coherent jet enshrouded in a supersonic fuel gas

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International Journal of Minerals,Metallurgy and Materials 2020年第2期27卷 173-180页

作者： Fei Zhao Rong zhu wen-rui Wang Key Laboratory of Fluid Interaction with Material University of Science and Technology BeijingBeijing 100083China National Center for Materials Service Safety University of Science and Technology BeijingBeijing 100083China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China School of Mechanical Engineer University of Science and Technology BeijingBeijing 100083China

Based on a current coherent jet,this study proposes a supersonic combustion(SC)coherent jet in which the main oxygen jet is surrounded by a supersonic fuel *** characteristics of the proposed coherent jet are analyzed using experimental methods and numerical simulations in the high-temperature environment of electric arc furnace(EAF)*** SC coherent jet achieved stable combustion in the EAF steelmaking *** simulated combustion temperature of the supersonic shrouding methane gas was 2930 K,slightly below the theoretical combustion temperature of methane–oxygen *** high speed and temperature of the supersonic flame effectively weakened the interaction between the main oxygen jet and the external ambient gas,inhibiting the radial expansion of the main oxygen jet and maintaining its high speed and low turbulence over a long *** features improved the impact capacity of the coherent jet and strengthened the stirring intensity in the EAF bath.

关键词： EAF steelmaking coherent jet supersonic shrouding fuel gas supersonic combustion field characteristics