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Spatiotemporal pulse weaving scalar optical hopfions

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Light(Science & Applications) 2023年第3期12卷 325-326页

作者： Chenhui Li Sicong Wang Xiangping Li Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications Institute of Photonics TechnologyJinan UniversityGuangzhouChina

Scalar optical hopfions weaved by nested equiphase lines in the shape of a toroidal vortex are theoretically designed and experimentally *** category of hopfions manifesting as a spatiotemporally structured pulse propagating in space-time may enable encoding and transferring optical topological information in an additional(temporal)dimension.

关键词： pulse optical enable

New Cembrane-Type Diterpenoids from the South China Sea Soft Coral Sinularia nanolobata

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Chinese Journal of Chemistry 2022年第1期40卷 28-38页

作者： Na Lin Heng Li Jian-Rong Wang Wei Tang Ming-Yue Zheng Hong Wang Cheng-Shi Jiang Yue-Wei Guo Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals and College of Pharmaceutical Science Zhejiang University of TechnologyHangzhouZhejiang 310014China State Key Laboratory of Drug Research Shanghai Institute of Materia MedicaChinese Academy of Sciences555 Zu Chong Zhi RoadZhangjiang Hi-Tech ParkShanghai 201203China Bohai rim Advanced Research institute for Drug Discovery Binhai East Road198#High-tech ZoneYantaiShandong 264000China School of Biological Science and Technology University of JinanJinanShandong 250022China

In the present study,nine new cembrane-type diterpenoids,namely ximaonanolobatins A—I(1—9),together with six related known analogs(10—15)and four known tetraprenylated alkaloids malonganenones D,E,H,and K(16—19)were isolated from the soft coral Sinularia nanolobata collected off the Ximao Island in the South China *** structures of 1—9 were robustly established by a combination of detailed spectroscopic analyses,chemical reactions,quantum mechanical(QM)-NMR methods,biogenetic consideration,and the comparison with those literature *** absolute configuration of 1 was confirmed by X-ray diffraction analysis,and the absolute configuration of 2 was determined by QM-NMR calculations and chemical *** addition,the absolute configuration of 3 was determined using the modified Mosher's *** these isolates were evaluated for their anti-inflammatory and anti-tumor *** results showed that only compound 15 exhibited potential anti-inflammatory effect against LPS-induced TNF-αrelease in RAW264.7 macrophages with an IC50 value of 12.6μmol/L.

关键词： Sinularia nanolobata Cembranoids X-ray diffraction Con figuration determination Natural products

The Establishment and Application of a Kraken Classifier for Salmonella Plasmid Sequence Prediction

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China CDC weekly 2022年第49期4卷 1110-1116页

作者： Zhenpeng Li Bo Pang Xin Lu Biao Kan State Key Laboratory of Infectious Disease Prevention and Control National Institute for Communicable Disease Control and PreventionChinese Center for Disease Control and PreventionBeijing MunicipalityChina School of Public Health Shandong UniversityJinan CityChina.

Introduction:Salmonella is a key intestinal pathogen of foodborne disease,and the plasmids in Salmonella are related to many biological characteristics,including virulence and drug resistance.A large number of plasmid contigs have been sequenced in bacterial draft genomes,however,these are often difficult to distinguish from chromosomal ***:In this study,three different customized Kraken databases were used to build three different Kraken *** genome benchmark datasets and simulated draft genome benchmark datasets were ***-fold cross-validation was used to evaluate the performance of the three different Kraken classifiers by two benchmark ***:The predictive performance of the classifier based on all National Center for Biotechnology Information plasmids and Salmonella complete genomes was *** optimal Kraken classifier was performed with Salmonella isolated in *** plasmid carrying rate of Salmonella in China is 91.01%,and it was found that the Kraken classifier could find more plasmid contigs and antibiotic resistance genes(ARGs)than results derived from a plasmid replicon-based method(PlasmidFinder).Moreover,it was found that in the strains carrying ARGs,plasmids carried more ARGs[three,95%confidence interval(CI):1–14]than chromosomes(one,95%CI:1–7).Discussion:We found building a high-quality customized database as a Kraken classifier to be ideal for the prediction of Salmonella plasmid sequences from bacterial draft *** the future,the Kraken classifier established in this study will play a significant role in ARG monitoring.

关键词： classifier database Application

Influence of surface charges on the emission polarization properties of single CdSe/CdS dot-in-rods

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Frontiers of physics 2019年第6期14卷 73-82页

作者： Guo-Feng Zhang Chang-Gang Yang Yong Ge Yong-Gang Peng Rui-Yun Chen Cheng-Bing Qin Yan Gao Lei Zhang Hai-Zheng Zhong Yu-Jun Zheng Lian-Tuan Xiao Suo-Tang Jia State Key Laboratory of Quantum Optics and Quantum Optics Devices Institute of Laser Spectroscopyand Collaborative Innovation Center of Extreme OpticsShanxi UniversityTaiyuan 030006China Beijing Key Laboratory of Nanophotonics and Ultrafine Optoelectronic Systems School of Materials Science and EngineeringBeijing Institute of TechnologyBeijing 100081China School of Physics Shandong UniversityJinan 250100China

We report an experimental investigation of the influence of surface charges on the emission polarization properties of single CdSe/CdS dot-in-rods(DRs),which is important for their polarization-based practical *** covering the single DRs with N-type semiconductor indium tin oxide(ITO)nanoparticles,the surface of single DRs is charged by ITO through interracial electron *** is confirmed by the experimental observations of the reduced photoluminescence intensities and lifetimes as well as the suppressing *** is found that the full width at half maximum of histogram of polarization degrees of the single DRs is broadened from 0.24(on glass)to 0.41(in ITO).In order to explain the exprimental results,the band-edge exciton fine structure of single DRs is calculated by taking into account the sample parameters,the emission polarization,and the surface *** calculation results show that the level ordering of the emitting states determines the polarization degrees tending to increase or decrease under the influence of surface *** surface electrons can induce an increase in the spacing between the emitting levels to change the populations and thus change the polarization *** addition,different numbers of surface electrons may randomly distribute on the long CdSe/CdS rods,leading to the heterogeneous influences on the single DRs causing the broadening of polarization degrees also.

关键词： single CdSe/CdS dot-in-rods polarization properties surface charges band-edge exciton fine structure

Biomass and Nutrient Accumulation Characteristics of Young Stands of Alnus cremastogyne

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Agricultural Biotechnology 2018年第1期7卷 50-54页

作者： Anmin MIN Yong WANG Xingliang LIU Yu WANG Li WANG Hongxia LI Xiaohu CAI Yongming AN Sichuan Academy of Forestry Science Chengdu 610081 China Aba Prefecture bureau of Forestry Maerkang 624000 China institute of Scenery Garden Management of urban and Rural planning Construction and Housing Security Bureau in Zitong County Zitong 622150 China

To investigate plant biomass and nutrient distribution and accumulation in organs of Alnus cremastogyne at different ages from 1 to 4 years, the biomass, N, P, K, Ca, Mg, Fe and Zn were tested. The results showed that the average biomass of the whole tree and the biomass of leaf, branch, stem, and root were in positive correlation with tree age, but the growth rate of biomass had a decreasing trend with the tree age increasing, and only the biomass proportion of the trunk in the whole individual plant showed an increasing trend with age. The contents of nutrient elements in organs showed an order of N 〉 Ca 〉 K 〉 Mg 〉 P 〉 Fe 〉 Zn ; and the contents of N, P and K were higher in the leaf than in other organs, and the contents of Ca, Mg and Fe in the root were higher than in other organs. The accumulations of N, P, K, Ca, Mg and Zn were the highest in the trunk, and that of Fe was the highest in the root. The annual net accumulations of N, P, K, Ca and Mg in the average trees from 1 to 4 years old were 17.07, 40.79, 95.82 and 106.71 g, respectively, and the annual net accumulations of microelements （Fe and Zn） were 335.04, 577.26, 1267 and 1525.27 mg, respectively.

关键词： Alnus cremastogyne Forest stands at different ages Demands for nutrient elements Biomass Nutrient elements

YSO coded aperture camera based on depth of interaction for location correction

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Radiation Detection Technology and Methods 2023年第4期7卷 589-598页

作者： Yiding Han Xiaopan Jiang Haohui Tang Xiuzuo Liang Xuanhou Hu Xianchao Huang Zhiming Zhang Lei Shuai Jing Guo Long Wei Beijing Engineering Research Center of Radiographic Techniques and Equipment Institute of High Energy PhysicsChinese Academy of SciencesBeijing100049China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing100049China jinan Laboratory of Applied Nuclear Science Jinan250131China CAEA Center of Excellence on Nuclear Technology Applications for Nuclear Detection and Imaging TaiyuanChina

Purpose Coded aperture imaging was a widely used imaging method for radiation ***,the traditional gamma camera based on two-dimensional projection information for coded aperture imaging ignored the influence of the interaction depth of particles and detectors on the projection information,which reduced the imaging quality of the camera to some ***,a method of correcting the coded gamma camera based on the interaction depth of particles and detectors is proposed to improve the location accuracy of *** The camera developed in this work uses a 7×7 YSO crystal array coupled with two 7×7 Si-PM *** crystal is evenly divided into 11 parts in the depth direction,with a voxel size of 3×3×3 *** coded mask is a 13×13 array,which is a mosaic of two cycles of 7×7 modified uniformly redundant array *** depth resolution of the detector is obtained via the subsurface laser engraving dual-end readout *** obtaining the three-dimensional position information of the interaction point the projection information obtained by the detector is layered,and the image is *** to the spatial position information of the detector and the coded mask,the corresponding field of view of each layer of the detector is calculated,and the reconstructed image of each layer is amplified and superimposed according to the ratio of the field of view to obtain the reconstructed image combined with the depth *** and conclusion According to Monte Carlo simulation and radiation source imaging experiment results,this method can effectively improve the positioning ability of the *** the experimental scenario mentioned in the paper,the location accuracy can be improved by up to 1.54°.

关键词： Depth of interaction Coded aperture gamma camera YSO detector Location accuracy

A comparative study of biopolymers and alum in the separation and recovery of pulp fibres from paper mill effluent by flocculation

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Journal of Environmental Sciences 2014年第9期26卷 1851-1860页

作者： Sumona Mukherjee Soumyadeep Mukhopadhyay Agamuthu Pariatamby Mohd. Ali Hashim Jaya Narayan Sahu Bhaskar Sen Gupta institute of Biological Sciences University of Malaya50603 Kuala LumpurMalaysia Department of Chemical Engineering University of Malaya50603 Kuala LumpurMalaysia Department of Petroleum and Chemical Engineering Faculty of EngineeringInstitute Teknologi BruneiTungku GadongBrunei Darussalam School of planning Architecture and Civil EngineeringQueen's University BelfastDavid Keir BuildingBelfast BT9 5AGUK

Recovery of cellulose fibres from paper mill effluent has been studied using common polysacchatides or biopolymers such as Guar gum, Xanthan gum and Locust bean gum as flocculent. Guar gum is commonly used in sizing paper and routinely used in paper making. The results have been compared with the performance of alum, which is a common coagulant and a key ingredient of the paper industry. Guar gum recovered about 3.86 mg/L of fibre and was most effective among the biopolyrners. Settling velocity distribution curves demonstrated that Guar gum was able to settle the fibres faster than the other biopolymers; however, alum displayed the highest particle removal rate than all the biopolymers at any of the settling velocities. Alum, Guar gum, Xanthan gum and Locust bean gum removed 97.46%, 94.68%, 92.39% and 92.46% turbidity of raw effluent at a settling velocity of 0.5 cm/min, respectively. The conditions for obtaining the lowest sludge volume index such as pH, dose and mixing speed were optimised for guar gum which was the most effective among the biopolymers. Response surface methodology was used to design all experiments, and an optimum operational setting was proposed. The test results indicate similar performance of alum and Guar gum in terms of fioc settling velocities and sludge volume index. Since Guar gum is a plant derived natural substance, it is environmentally benign and offers a green treatment option to the paper mills for pulp recycling.

关键词： BiopolymerRecovery of fibresGuar gumFlocculationPaper industry

Suggestions on the Effective Development of Shale Gas in China

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China Oil & Gas 2018年第4期25卷 18-25页

作者： Cao Yan Yang Kefeng Jing Keyao Hu Yan Sinopec Petroleum Exploration and Production Research institute Development & planning Department Sinopec Group

Shale gas is a practical resource with great potential that could be economically explored and developed in the near future. It has been commercially developed in North America and other places. Featuring a vast distribution, a low abundance,unfavorable reservoir conditions, ultra-low permeability and a fast production decline, shale gas is more difficult to develop than conventional natural gas, as it needs advanced drilling and completion technology to develop. During the early stage of shale gas exploration and development, the United States offered enterprises necessary incentives such as tax reductions and exemptions and subsidies to achieve sustainable shale gas development and encourage technological progresses. By comparing the state of China's shale gas development with that of the US' in terms of geological conditions, production technology,market price, tax relief, subsidy periods and amount, this paper intends to put forward related suggestions for the effective development of shale gas according to the current status of development.

关键词： Unconventional resource Shale gas Effective development Subsidy period Subsidy Suggestion

Observation of “Outlaw” Dual Aromaticity in Unexpectedly Stable Open-Shell Metal Clusters Caused by Near-Degenerate Molecular Orbital Coupling

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CCS Chemistry 2021年第7期3卷 1913-1920页

作者： Jun Li Jing Wang Jing Chen Yu-Xiang Bu Shi-Bo Cheng School of Chemistry and Chemical Engineering Shandong UniversityJinan 250100 Suzhou institute of Shandong University Suzhou 215123 School of Chemistry and Chemical Engineering Qufu Normal UniversityQufu 273165

The Hückel’s rule,Baird’s rule,and electronic shell closure model are classical and well-established concepts in chemistry,which have long been employed in rationalizing the aromaticity/antiaromaticity of organic species and stability of inorganic ***,the observation of unique species featuring properties out of the fundamental frameworks of these rules is challenging but significant and helps in drawing a complete picture of fascinating concepts in chemistry.

关键词： relative stability aromaticity inorganic metal clusters density functional theory calculations near-degenerate molecular orbital coupling electronic shell closure model