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The classification of plants by laser-induced breakdown spectroscopy based on two chemometric methods

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Plasma Science and Technology 2020年第7期22卷 92-97页

作者： zhongqi feng Dacheng ZHANG Bowen WANG Jie DING Xuyang LIU Jiangfeng ZHU School of Physics and Optoelectronic Engineering Xidian UniversityXi’an 710071People’s Republic of China

The applications of laser-induced breakdown spectroscopy(LIBS) on classifying complex natural organics are relatively limited and their accuracy still requires *** this work,to study the methods on classification of complex organics,three kinds of fresh leaves were measured by LIBS.100 spectra from 100 samples of each kind of leaves were measured and then they were divided into a training set and a test set in a ratio of 7:*** algorithms of chemometric methods including the partial least squares discriminant analysis(PLS-DA) and principal component analysis Mahalanobis distance(PCA-MD) were used to identify these *** using 23 lines from 16 elements or molecules as input data,these two methods can both classify these three kinds of leaves *** classification accuracies of training sets are both up to 100% by PCA-MD and *** classification accuracies of the test set are 93.3% by PCA-MD and 97.8% by *** means that PLS-DA is better than PCA-MD in classifying plant *** the components in PLS-DA process are more suitable for classification than those in PCA-MD *** think that this work can provide a reference for plant traceability using LIBS.

关键词： laser-induced breakdown spectroscopy principal component analysis Mahalanobis distance partial least squares discriminant analysis classification of complex organics

O-GlcNAcylation of YTHDF2 promotes HBV-related hepatocellular carcinoma progression in an N^(6)-methyladenosine-dependent manner

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Signal Transduction and Targeted Therapy 2023年第3期8卷 1208-1223页

作者： Yang Yang Yu Yan Jiaxin Yin Ni Tang Kai Wang Luyi Huang Jie Hu zhongqi feng Qingzhu Gao Ailong Huang Institute for Viral Hepatitis Key Laboratory of Molecular Biology for Infectious Diseases(Ministry of Education)Department of Infectious DiseasesThe Second Affiliated HospitalChongqing Medical UniversityChongqingChina

Hepatitis B virus(HBV)infection is a major risk factor for hepatocellular carcinoma(HCC),but its pathogenic mechanism remains to be *** RNA N^(6)-methyladenosine(m^(6)A)reader,YTH(YT521-B homology)domain 2(YTHDF2),plays a critical role in the HCC ***,the function and regulatory mechanisms of YTHDF2 in HBV-related HCC remain largely ***,we discovered that YTHDF2 O-GlcNAcylation was markedly increased upon HBV infection.O-GlcNAc transferase(OGT)-mediated O-GlcNAcylation of YTHDF2 on serine 263 enhanced its protein stability and oncogenic activity by inhibiting its ***,YTHDF2 stabilized minichromosome maintenance protein 2(MCM2)and MCM5 transcripts in an m^(6)A-dependent manner,thus promoting cell cycle progression and HBV-related HCC ***,targeting YTHDF2 O-GlcNAcylation by the OGT inhibitor OSMI-1 significantly suppressed HCC *** together,our findings reveal a new regulatory mechanism for YTHDF2 and highlight an essential role of YTHDF2 O-GlcNAcylation in RNA m^(6)A methylation and HCC *** description of the molecular pathway has the potential to yield therapeutic targets for suppression of HCC progression due to HBV infection.

关键词： hepatocellular markedly DF2

Monolithic integrated optoelectronic chip for vector force detection

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Microsystems & Nanoengineering 2024年第3期10卷 245-257页

作者： Jiansong feng zhongqi Wang Mengyuan Zhanghu Xu Zhang Yong Shen Jing Yang Zhibin Li Bin Chen Taihong Wang Xiaolong Chen Zhaojun Liu Department of Electrical and Electronic Engineering Southern University of Science and TechnologyShenzhen 518055China Department of Electrical and Electronic Engineering The University of Hong KongHong KongChina

Sensors with a small footprint and real-time detection capabilities are crucial in robotic surgery and smart wearable *** device footprint while maintaining its high performance is a major challenge and a significant limitation to their ***,we proposed a monolithic integrated micro-scale sensor,which can be used for vector force *** sensor combines an optical source,four photodetectors,and a hemispherical silicone elastomer component on the same sapphire-based AlGaInP *** chip-scale optical coupling is achieved by employing the laser lift-off techniques and the flip-chip bonding to a processed sapphire *** hemispherical structure device can detect normal and shear forces as low as 1mN within a measurement range of 0–220 mN for normal force and 0–15 mN for shear *** packaging,the sensor is capable of detecting forces over a broader range,with measurement capabilities extending up to 10 N for normal forces and 0.2 N for shear *** has an accuracy of detecting a minimum normal force of 25 mN and a minimum shear force of 20 ***,this sensor has been validated to have a compact footprint of approximately 1.5 mm^(2),while maintaining high real-time *** also demonstrate its promising potential by combining this sensor with fine surface texture perception in the fields of compact medical robot interaction and wearable devices.

关键词： robot force smart

TEM STUDY OF BONDING LAYERS IN DISSIMILAR ALLOY EXPLOSIVE BONDING JOINTS

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Acta Metallurgica Sinica(English Letters) 1989年第4期2卷 237-243页

作者： ZHOU Bangxin SHENG zhongqi PENG feng Southwest Center for Nuclear Reactor Engineering Research and Design,Chengdu,China P.O.Box 291-601,Chengdu,Sichuan,China

The bonding layers in dissimilar alloy explosive bonding joints,γ/α stainless steels, copper/carbon steel and brass/γ-stainless steel have been studied by means of TEM tech- *** results show that the bonding is obtained by diffusion and local melting at the con- tact *** structure of bonding layer not only responds to the compositions of the bond- ing alloys,but also the difference between their thermal conductivities,melting points and recrystallization temperatures,Because of the small molten region and fast cooling rate,the structure of molten region could be amorphous or microcrystals,and both stable and metastable phases exsist.

关键词： explosive bonding electron microscope bonding layer

A novel method for AFRPs burrs removal:Principle of mechanochemo-induced fiber fracture

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Chinese Journal of Aeronautics 2024年第7期37卷 522-538页

作者： Jie XU Bo LI Pingfa feng Qiang WANG feng feng Division of Advanced Manufacturing Tsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055China Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China Changhe Aircraft Industry(Group)Co.Ltd Jingdezhen 333000China

Burrs generated during the machining of Aramid-Fiber-Reinforced Composites(AFRPs)pose a challenge for the production efficiency of aircraft and helicopter housing *** studies have generally attempted to suppress burrs by referring to delamination suppression *** contrast to stratification,burrs are remediable machining *** such,a mechanochemical method with burrs trimming technological strategy are implemented to effectively combat ***,we clarify the mechanism by which aramid fibers cannot be cut off using analytical and numerical *** addition,the mechanism of fiber fracture with Modified Polyurethane Reactive Polymer(M-PUR),and development of anti-burr devices(thermostatic adhesive sealed generator)are ***,the experimental results show that the reduction rate in burr length is 87%-91%through the mechanochemical *** method not only opens a new avenue to solve the burr problem of aramid fibers but also builds an interdisciplinary bridge between polymer science and composite machining.

关键词： Mechanochemical method Burrs Orthogonal cutting Aramid fiber-reinforced composites Milling

Record-high efficiency perovskite LEDs achieved by accelerating radiative recombination

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Science China Materials 2024年第9期67卷 3039-3040页

作者： feng Gao Department of Physics Chemistry and BiologyLinköping UniversityLinköping58183Sweden

Light-emitting diodes(LEDs)have revolutionized the lighting and displays due to their superior energy *** increasing demand for more efficient and brighter thin-film LEDs in flat-panel displays and solid-state lighting applications has driven extensive research into perovskite materials,which show great promise for high brightness and efficiency.

关键词： lighting radiative high

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Derivation of Expanded Isospectral-Nonisospectral Integrable Hierarchies via the Column-vector Loop Algebra

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Acta Mathematicae Applicatae Sinica 2024年第3期40卷 778-800页

作者： Hai-feng WANG Yu-feng ZHANG School of Science Jimei UniversityXiamen 361021China School of Mathematics China University of Mining and TechnologyXuzhou 221116China

A scheme for generating nonisospectral integrable hierarchies is *** on the method,we deduce a nonisospectral hierarchy of soliton equations by considering a linear spectral *** follows that the corresponding expanded isospectral and nonisospectral integrable hierarchies are deduced based on a 6 dimensional complex linear space ■.By reducing these integrable hierarchies,we obtain the expanded isospectral and nonisospectral derivative nonlinear Schr?dinger *** using the trace identity,the biHamiltonian structure of these two hierarchies are also ***,some symmetries and conserved quantities of the resulting hierarchy are discussed.

关键词： expanded isospectral-nonisospectral integrable hierarchies column-vector loop algebra bi-Hamiltonian structure symmetry

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Carbon-based materials with combined functions of thermal management and electromagnetic protection: Preparation, mechanisms, properties, and applications

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Nano Research 2024年第3期17卷 883-903页

作者： Junwei Yue Yiyu feng Mengmeng Qin Wei feng School of Materials Science and Engineering and Tianjin Key Laboratory of Composite and Functional Materials Tianjin UniversityTianjin 300350China

The proliferation of high-power,highly informationized,and highly integrated electronic devices and weapons equipment has given rise to increasingly conspicuous issues about electromagnetic(EM)pollution and thermal *** issues,in turn,impose constraints on the performance of such equipment and jeopardize personnel *** materials,owing to their diverse and modifiable structures,offer adjustable thermal and electric conductivity,rendering them highly promising for applications in fields such as thermal management and EM protection which have garnered extensive research and *** pursuit of integrated device and equipment development has elevated the demand for multifunctional materials,prompting significant research into carbon-based composite materials that include both thermal management and EM protection ***,there are no relevant reviews on this topic at ***,this work consolidates research findings from recent years on carbon matrix composites exhibiting dual attributes of thermal management and EM *** attributes include thermally conductive electromagnetic interference(EMI)shielding materials,thermally insulating EMI shielding materials,thermally conductive EM wave(EMW)absorbing materials,and thermally insulating EMW absorbing *** paper elucidates the fundamental principles underpinning thermal conduction,thermal insulation,EMW absorbing,and EMI ***,it engages in discussions surrounding areas of contention,design strategies,and the functional properties of various material ***,the paper concludes by presenting the challenges encountered and potential research strategies about composites endowed with both thermal management and EM protection functionalities,while also envisaging the development of novel multifunctional EM protection materials.

关键词： carbon-based composites electromagnetic interference shielding microwave absorption thermal conduction thermal insulation

Design and identification of a double-acting piezoelectric-hydraulic hybrid actuator

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Chinese Journal of Aeronautics 2024年第3期37卷 456-467页

作者： Junjian ZHANG Zhihua feng Key Laboratory of Precision Scientific Instrumentation of Anhui Higher Education Institutes University of Science and Technology of ChinaHefei 230026China

Traditional single-acting piezoelectric-hydraulic hybrid actuators usually have the problem of inertial force caused by flow pulsation of the liquid,which degrades their output *** suppress or solve the associated inertial force and enhance its output capabilities,this paper proposes a new type of double-acting piezoelectric-hydraulic hybrid actuator with four check valves acting as mechanical *** new hybrid actuator was fabricated and its output performance was *** the voltage is 700 Vp-pand the bias pressure is 2 MPa,the pulsation ratesδof the new actuator at 400 Hz,500 Hz and 600 Hz are 2.29,2.08 and 1.78,respectively,whileδof the single-acting hybrid actuator under the same conditions are 10.98,11.05 and ***,the liquid pulsation rate of the new hybrid actuator is significantly reduced,which is beneficial for improving the flow uniformity and weakening the influence of inertial force on the hybrid *** strategy ultimately leads to a maximum no-load velocity of 168.1 mm/s at 600 Hz and a maximum blocking force of 141 N at 450 Hz for the new hybrid *** addition,this strategy has the potential to be used in other electrohydrostatic actuators to improve their performance.

关键词： Double-acting Flow pulsation Inertial force Piezoelectric actuators Piezoelectric devices Piezoelectric hydraulic actuation Piezoelectric pump