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Orbital angular momentum-mediated machine learning for high-accuracy mode-feature encoding

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light(Science & Applications) 2024年第3期13卷 466-477页

作者： Xinyuan Fang Xiaonan Hu Baoli li Hang Su Ke Cheng Haitao luan Min Gu Institute of Photonic Chips University of Shanghai for Science and TechnologyShanghai 200093China Centre for Artificial-Intelligence Nanophotonics School of Optical-Electrical and Computer EngineeringUniversity of Shanghai for Science and TechnologyShanghai 200093China

Machine learning with optical neural networks has featured unique advantages of the information processing including high speed,ultrawide bandwidths and low energy consumption because the optical dimensions(time,space,wavelength,and polarization)could be utilized to increase the degree of ***,due to the lack of the capability to extract the information features in the orbital angular momentum(OAM)domain,the theoretically unlimited OAM states have never been exploited to represent the signal of the input/output nodes in the neural network ***,we demonstrate OAM-mediated machine learning with an all-optical convolutional neural network(CNN)based on Laguerre-Gaussian(LG)beam modes with diverse diffraction *** proposed CNN architecture is composed of a trainable OAM mode-dispersion impulse as a convolutional kernel for feature extraction,and deep-learning diffractive layers as a *** resultant OAM mode-dispersion selectivity can be applied in information mode-feature encoding,leading to an accuracy as high as 97.2%for MNIST database through detecting the energy weighting coefficients of the encoded OAM modes,as well as a resistance to eavesdropping in point-to-point free-space ***,through extending the target encoded modes into multiplexed OAM states,we realize all-optical dimension reduction for anomaly detection with an accuracy of 85%.Our work provides a deep insight to the mechanism of machine learning with spatial modes basis,which can be further utilized to improve the performances of various machine-vision tasks by constructing the unsupervised learning-based auto-encoder.

关键词： polarization mode momentum

Investigation on Precooling Effects of 4 K Stirling-Type Pulse Tube Cryocoolers

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Journal of Thermal Science 2019年第4期28卷 714-726页

作者： CAO Qiang li Zimu luan Mingkai SUN Zheng TANG Xiao li Peng JIANG Zhenhua WEI li Institute of Refrigeration and Cryogenics School of Mechanical EngineeringTongji UniversityShanghai 201804China Shanghai Key Laboratory of Vehicle Aerodynamics and Vehicle Thermal Management Systems Tongji UniversityShanghai 201804China Shanghai Institute of Technical Physics Chinese Academy of SciencesShanghai 200083China Department of Electrical Engineering School of Electronics and Information EngineeringTongji UniversityShanghai 201804China

Stirling-type pulse tube cryocoolers(SPTCs)working at liquid-helium temperatures are appealing in space applications because of their promising advantages such as high reliability,compactness,*** efforts have been put in to develop SPTCs operating at liquid-helium temperatures especially with helium-4 as the working *** structure is essential to reach such low ***,both the regenerator of the last section and the pulse tube together with the phase shifter are precooled by its upper stage or by external cold source to a low temperature of around 20 ***,the precooling effects on the regenerator and the pulse tube are synthetic in previous studies,and their independent effects have not been studied *** this manuscript,the precooling effects on the regenerator and on the pulse tube together with the phase shifter are tested independently on a unique-designed precooled *** tested precooling temperature is between 13.3 K and 22 K,and the no-load refrigeration temperature gets down to 3.6 *** analyses and numerical calculations have been carried *** is found that the influence on the regenerator is remarkable,which is different from previous *** is also found that the precooling effects on the pulse tube are relatively weak because of the large pressure-induced enthalpy flow of a real gas working at the temperatures near to the critical ***,the phase shifting capacity is analyzed with two cases and with both helium-4 and helium-3 as working fluids,and it keeps quite constant after optimizing the frequency and the precooling temperature for each *** investigation on these independent effects will provide valid reference on the precooling mechanism study of SPTCs working down to liquid-helium temperatures.

关键词： stirling-type pulse tube cryocooler precooling effects liquid-helium temperatures

Size matters:Steric hindrance of precursor molecules controlling the evolution of CdSe magic-size clusters and quantum dots

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Nano Research 2022年第9期15卷 8564-8572页

作者： Juan Shen Chaoran luan Nelson Rowell Yang li Meng Zhang Xiaoqin Chen Kui Yu Institute of Atomic and Molecular Physics Sichuan UniversityChengdu 610065China Laboratory of Ethnopharmacology Tissue-orientated Property of Chinese Medicine Key Laboratory of Sichuan ProvinceWest China School of MedicineWest China HospitalSichuan UniversityChengdu 610065China Metrology Research Centre National Research Council CanadaOttawaOntario K1A 0R6Canada Engineering Research Center in Biomaterials Sichuan UniversityChengdu 610065China

little is known about how to precisely promote the selective production of either colloidal semiconductor metal chalcogenide(ME),magic-size clusters(MSCs),or quantum dots(QDs).Recently,a two-pathway model has been proposed to comprehend their evolution;here,we reveal for the first time that the size of precursors plays a decisive role in the selected evolution pathway of MSCs and *** the reaction of cadmium myristate(Cd(MA)2)and tri-n-octylphosphine selenide(SeTOP)in 1-octadecene(ODE)as a model system,the size of Cd precursors was manipulated by the steric hindrance of carboxylic acid(RCOOH)*** RCOOH,the reaction produced both CdSe MSCs and QDs(from 100 to 240℃).With RCOOH,the reaction produced MSCs or QDs when R was small(such as CH3−)or large(such as C6H5−),*** to the twopathway model,the selective evolution is attributed to the promotion and suppression of the self-assembly of Cd and Se precursors,*** propose that the addition of carboxylic acid may occur ligand exchange with Cd(MA)2,causing the different sizes of Cd *** results suggest that the size of Cd precursors regulates the self-assemble behavior of the precursors,which dictates the directed evolution of either MSCs or *** present findings bring insights into the two-pathway model,as the size of M and E precursors determine the evolution pathways of MSCs or QDs,the understanding of which is of great fundamental significance toward mechanism-enabled design and predictive synthesis of functional nanomaterials.

关键词： cadmium selenide(CdSe) magic-size clusters(MSCs) quantum dots(QDs) self-assembly steric hindrance

Trifunctionalization of Aryl Iodides with Two Distinct Nitrogen and Carbon Electrophiles by Palladium/Norbornene Catalysis

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Chinese Journal of Chemistry 2021年第10期39卷 2659-2667页

作者： Jing Wang Hui Wang Zihan Wang linqiang li Cheng Qin Xinjun luan Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education College of Chemistry&Materials ScienceNorthwest UniversityXi'anShaanxi710127 China

Main observation and conclusion Herein,we report a highly chemo-and regioselective vicinal trifunctionalization of aryl iodides by palladium/norbornene(Pd/NBE)*** key feature of this new method is the introduction of two distinct nitrogen and carbon electrophiles,with a large gap in reactivity,for ortho-unsubstituted aryl iodides via an intermolecular and intramolecular C―H functionalization,*** types of ipso terminations can be coupled with both ortho-amination and ortho-alkylation,affording a variety of polysubstituted benzoheterocyclic ***-tethered substrates can lead to polyfucntional arenes via a single-step ***,these products exhibit full-color-tunable strong fluorescence emissions with large Stokes shifts,and product 7r can serve as a fluorescent probe to specifically target lysosome in living cells.

关键词： Trifunctionalization C-H activation Polyfunctional arenes Norbornene Palladium

Astronomical forcing and sedimentary noise modeling of lake-level changes in the Middle Eocene Chezhen Sag,Bohai Bay Basin,eastern China

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Frontiers of Earth Science 2024年第2期18卷 446-459页

作者： Xuwei luan Jinliang ZHANG Na li Tao CHEN Long SUN Xuecai ZHANG Faculty of Geographical Science Beijing Normal UniversityBeijing 100875China College of Geosciences China University of Petroleum(Beijing)Beijing 102249China Management Center of Oil and Gas Exploration Sinopec Shengli OilfieldDongying 257000China

The accurate determination of geological age is a key to understanding the history and process of paleolake evolution and oil and gas exploration in continental lake ***,improving the accuracy of geological age has always been a difficult scientific problem.A 609-m-thick,continuous lacustrine mudstone and sandstone succession in Chezhen Sag(eastern China)provides an ideal middle Eocene sedimentary record for establishing a high-resolution stratigraphic chronology *** on spectrum analysis and sliding window spectrum analysis of the natural gamma(GR)logging data of well Che 271(C271)in Chezhen Sag,the periods of 405 kyr and 40.1 kyr were filtered by a Gaussian bandpass filter,and a“floating”astrochronological time scale(ATS)was *** total number of 405 kyr eccentricity cycles were 13.6 and 40.1 kyr obliquity cycles were 138 which recorded from the upper member 4(Es4U)to the member 3(Es3)of the Eocene Shahejie Formation,and the depositional duration was 5.53 *** Coefficient(COCO)analysis and evolutionary Correlation Coefficient(eCoCo)analysis found that the optimal sedimentary rate of different *** noise simulation revealed the history of paleolake water changes in the Middle Eocene in the Chezhen Sag,according to which four sequences are *** study shows that the lake level change of Chezhen Sag in the middle Eocene shows prominent 1.2 Myr cycles and an antiphase well-coupled relationship with obliquity ***,we propose a model to explain the relationship between the orbital cycle and lake level change in the continental lake *** the obliquity of the earth increases,the middle and high latitudes of the earth will be closer to the sun,the direct sunlight will be higher,and the meridional sunshine will increase,thus accelerating the evaporation process of lake basin *** the seasonal changes are obvious(maximum period of 1.2 Myr ultra-long obliquity),this effect is more signific

关键词： Chezhen Sag cyclostratigraphy astrochronological time scale sedimentary noise

Ir0/graphdiyne atomic interface for selective epoxidation

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National Science Review 2023年第8期10卷 173-179页

作者： Zhiqiang Zheng Lu Qi Yaqi Gao Xiaoyu luan Yurui Xue Feng He Yuliang li Shandong Provincial Key Laboratory for Science of Material Creation and Energy Conversion Science Center for Material Creation and Energy Conversion School of Chemistry and Chemical EngineeringShandong University CAS Key Laboratory of Organic Solids Institute of ChemistryChinese Academy of Sciences School of Chemical Sciences University of Chinese Academy of Sciences

The development of catalysts that can selectively and efficiently promote the alkene epoxidation at ambient temperatures and pressures is an important promising path to renewable synthesis of various chemical products. Here we report a new type of zerovalent atom catalysts comprised of zerovalent Ir atoms highly dispersed and anchored on graphdiyne(Ir0/GDY) wherein the Ir0is stabilized by the incomplete charge transfer effect and the confined effect of GDY natural cavity. The Ir0/GDY can selectively and efficiently produce styrene oxides(SO) by electro-oxidizing styrene(ST) in aqueous solutions at ambient temperatures and pressures with high conversion efficiency of ～100%, high SO selectivity of 85.5%, and high Faradaic efficiency(FE) of 55%. Experimental and density functional theory(DFT) calculation results show that the intrinsic activity and stability due to the incomplete charge transfer between Ir0and GDY effectively promoted the electron exchange between the catalyst and reactant molecule, and realized the selective epoxidation of ST to SO. Studies of the reaction mechanism demonstrate that Ir0/GDY proceeds a distinctive pathway for highly selective and active alkene-to-epoxide conversion from the traditional processes. This work presents a new example of constructing zerovalent metal atoms within the GDY matrix toward selective electrocatalytic epoxidation.

关键词： graphdiyne atom catalyst atomic interface selective epoxidation high-performance

Study on gas–liquid flow characteristics in stirred tank with dual-impeller based on CFD-PBM coupled model

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Chinese Journal of Chemical Engineering 2021年第10期34卷 63-75页

作者： Songsong Wang Qiuxiang Bu Deyu luan Ying Zhang Longbin li Zhaorui Wang Wenhao Shi College of Electromechanical Engineering Qingdao University of Science and TechnologyQingdao 266061China

Study on gas–liquid flow in stirred tank with two combinations of dual-impeller(six-bent-bladed turbine(6BT)+six-inclined-blade down-pumping turbine(6 ITD),the six-bent-bladed turbine(6BT)+six-inclinedblade up-pumping turbine(6ITU))was conducted using computational fluid dynamics(CFD)and population balance model(PBM)(CFD-PBM)coupled *** local bubble size was captured by particle image velocimetry(PIV)*** gas holdup,bubble size distribution and gas–liquid interfacial area were explored at different conditions through numerical *** results showed that the 4 mm bubbles accounted for the largest proportion of 33%at the gas flow rates Q=0.76 m^(3)·h^(-1) and 22%at Q=1.52 m^(3)·h^(-1) for combined impeller of 6BT+6ITU,while the bubbles of 4.7 mm and 5.5 mm were the largest proportion for 6BT+6ITD combination,i.e.25%at Q=0.76 m^(3)·h^(-1) and 22%at Q=1.52 m^(3)·h^(-1),respectively,which indicated that 6BT+6ITU could reduce bubble size effectively and promote gas *** addition,the gas holdup around impellers was increased obviously with the speed compared with gas flow *** it was concluded that 6ITU impeller could be more conductive to the bubble dispersion with more uniform bubble size,which embodied the advantages of 6BT+6ITU combination in gas–liquid mixing.

关键词： Gas-liquid two-phase flow Gas holdup Gas-liquid interfacial area Bubble Coupling algorithm of CFD-PBM

Synthesis of ordered hierarchically mesoporous/microporous carbon materials via compressed CO_(2) for fructose-to-HMF transformation

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Green Energy & Environment 2022年第5期7卷 1033-1044页

作者： Sen luan Wei li Zanwu Guo Wenxiu li Xiaojian Hou Yi Song Ran Wang Qian Wang Department of Chemistry Capital Normal UniversityBeijing100048China

Well-ordered hierarchically mesoporous/microporous carbon materials have been successfully fabricated by using dual soft-templating approach through compressed CO_(2).Pluronic F127 and different type of surfactants,including nonionic,cationic,and anionic surfactants,were used as dual templates to investigate the influence on the morphology and nanostructure of the as-prepared carbon ***,SEM,N2 sorption,wide-angle and small-angle XRD analysis were employed to reveal the well-ordered hierarchically micro-mesoporous structure with2 D hexagonal symmetry by using compressed CO_(2).The prepared HPC samples with different pressures as the catalyst carriers have been functioned by chlorosulfonic acid for the fructose conversion into *** acid concentration,catalyst dosage and reaction temperature have been optimized for fructose-to-HMF transformation with the obtained *** performances of as-made HPC-SO_(3) H samples in HMF yield and reaction rate of fructose-to-HMF transformation have been *** stability of the samples was also conducted in the dehydration of fructose to HMF for five *** possible catalytic mechanism by using hierarchically porous carbon materials as catalyst support for fructose-to-HMF transformation was proposed.

关键词： ordered catalyst carbon

Efficacy of a Nutritional Cream Intervention to Treat Depression in Rescuers:A Randomized Controlled Trial

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Biomedical and Environmental Sciences 2024年第7期37卷 754-761页

作者： Qiao Wang Hengyu luan Chunyan li Rufang Gong Qiongxuan li Jiayi Deng Xiaoyong Sai Department of Statistics and Epidemiology The Graduate School of the Chinese PLA General HospitalBeijing 100853China Comprehensive Internal Medicine Western Medical Branch of PLA General HospitalBeijing 100144China Department of Respiratory The First Medical Center of PLA General HospitalBeijing 100853China Department of Pharmacy Intravenous Admixture Services(PIVAS) The First Medical Center of PLA General HospitalBeijing 100853China

Objective To explore the effectiveness of a nutritional intervention in rescuers who screened positive for *** A randomized controlled trial design was *** June to August,2022,4,460 rescuers were screened using the Self-Rating Depression Scale(SDS),and 1,615 positive cases were ***-one volunteers were recruited and randomly divided into a nutritional intervention group and a control *** intervention group received health education and nutritional intervention(a compound paste therapy primarily composed of red roses and Seville orange flowers),while the control group received psychological *** scores were assessed before and after the *** There was a statistically significant decline in SDS scores in the nutritional intervention group after the intervention(P<0.05).Furthermore,the SDS scores of the intervention group were significantly lower than those of the control group,both before and after the intervention(P<0.05).No severe adverse reactions were observed during safety *** The nutritional intervention effectively reduced the depression scores in *** nutritional intervention is recommended for rescuers who initially screen positive for depression.

关键词： Nutritional intervention Rescuers Depression Randomized controlled trial