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Selection of Suitable Area and Analysis of Adaptability Difference of Prunus humilis

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Asian Agricultural Research 2024年第3期16卷 41-45页

作者： Ze YAO Shengxiu JIANG Zizhu YAN Qi wang dawei wang Gansu Desert Control Research Institute Lanzhou 730700China Gansu Psammophytes Engineering Technology Research Center Lanzhou 730700China State Key Laboratory of Desertification and Aeolian Sand Disaster Combating Lanzhou 730700China

This paper delves into and assesses the differences in biological traits and fruit nutritional composition of 3 varieties of Prunus humilis introduced from 2 different regions.Results showed that(i)the contents of protein,total sugar,and calcium of No.5 variety were higher those of the other 2 varieties,which was recognized as the most suitable variety for fresh fruit;(ii)the comparison of leaf areas index and fruit shape index of 3 varieties shows that the fruit shape index and individual fruit weight of the introduced varieties were higher than those of the control,the diameter of individual fruit of the introduced varieties higher than that of the control indicated that they had a higher fruit hardness,more dry matter accumulation and better fruit quality,and that the introduction region was more suitable for scale-up of P.humilis;(iii)there was a positive correlation with the number of fruiting branches and there was a significant negative correlation with individual fruit weight,while the leaf area had a significant negative correlation with the number of fruiting branches.The introduced varieties can develop normally in the 2 testing areas,notably,No.5 variety performed better than No.4 and No.6.Improving management is the prerequisite for maintaining proper number of fruiting branches and high yield.

关键词： Prunus humilis Biological traits Nutritional components Introduction and cultivation

Research Progress of QuEChERS Pretreatment Technique in the Detection of Multiple Pesticide Residues

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Agricultural Biotechnology 2024年第2期13卷 10-11,37页

作者： Bo LIU dawei wang Yuhang GUO Xuehua wang Lei wang Yajuan SONG Tangshan Food and Drug Comprehensive Testing Center Tangshan 063000China Hebei Agricultural Products Quality and Safety Testing Innovation Center Tangshan 063000China

The QuEChERS extraction technique is a pretreatment technique that has been rapidly applied in recent years and is widely used in the field of pesticide residues with many advantages. This technique is based on solid phase extraction (SPE), which uses the interaction between adsorbent and impurities in the matrix to achieve the purpose of purification. The method has easier operation and better purification effect than SPE. In this paper, the research progress of the QuEChERS technique in pesticide residue detection in different fields in recent years and its future development were reviewed, hoping to provide reference for further development and utilization of the QuEChERS technique in pesticide residue detection in the future.

关键词： QuEChERS Pretreatment Pesticide residues Research progress

Laser Wire Additive Manufacturing of Ti-6Al-4V Alloy and Its Machine Learning Study for Parameters Optimization(Invited)

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中国激光 2024年第4期51卷 182-198页

作者： Wu Junyi Zhang Bo wang Weihua Li Weipeng Yao Xiyu wang dawei Xing Wei Yan Ming Department of Materials Science and Engineering Southern University of Science and TechnologyShenzhen 518055GuangdongChina Songshan Lake Materials Laboratory Dongguan 523830GuangdongChina Institute of Physics Chinese Academy of SciencesBeijing 100190China Jiaxing Research Institute Southern University of Science and TechnologyShenzhen 518055GuangdongChina High Performance Computing Department National Supercomputing CenterShenzhen 518055GuangdongChina

Ti-6Al-4V is a benchmark Ti alloy. Laser wire additive manufacturing(LWAM) offers advanced manufacturing capability to the alloy for applications possibly including exploration of outer space. As a typical multiple-variable process, LWAM is complex, which, however, can be analyzed, predicated or even optimized by artificial intelligence(AI) methods such as machine learning(ML). In this study, printing parameters of the Ti-6Al-4V is firstly optimized using single-track-single-layer experiments, and then single-track-multiple-layer samples are printed, whose properties in terms of hardness and compressive strength are analyzed subsequently by both experiments and ML. The two ML approaches, artificial neural network(ANN) and support vector machine(SVM), are employed to predict the experimental results, whose coefficients of determination R2 show good values. Further optimized properties are realized by adopting genetic algorithm(GA) and simulated annealing(SA) approaches, which contribute to high mechanical properties achieved, for instance, an engineering compressive strength of about 1694 MPa. The results here indicate that important mechanical properties of the LWAM-prepared Ti alloys can be well predicted and enhanced using suitable ML approaches.

关键词： artificial printing additive

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The scoping study of Kazakhstan-China-Republic of Korea power interconnection

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Global Energy Interconnection 2022年第5期5卷 484-500页

作者： Xiaomeng Lei dawei wang Wei wang China Electricity Council Beijing 100761P.R.China Global Energy Interconnection Development and Cooperation Organization Beijing 100031P.R.China

Electric interconnection is an essential trend for future large-scale development and utilization of renewable energy.China has proposed the concept of Global Energy Interconnection to realize the clean utilization of energy through the interconnection of power grids and optimize the allocation of global energy resources.This study proposes the Kazakhstan-China-Republic of Korea networking scheme,analyzing the characteristics of power supply and demand in these countries.Based on the regional economic analysis and power development,four interconnection schemes are proposed utilizing UHVDC technology.Accordingly,existing problems and favorable factors are fully considered.The investment analysis of±1100 kV and±800 kV lines,configuration scheme of the converter station,and investment estimation of four interconnection schemes are given.

关键词： Global Energy Interconnection Renewable energy source Interconnection schemes Cost and benefits analysis.

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An efficient graph data compression model based on the germ quotient set structure

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Frontiers of Computer Science 2022年第6期16卷 195-197页

作者： dawei wang Wanqiu CUI Regional Innovation and Development Research Center Institute of Scientific and Technical Information of ChinaBeijing100038China School of National Security People’s Public Security University of ChinaBeijing100038China

1 Introduction The graph data model is a crucial foundation of the graph database and has been extensively applied with relational data,such as knowledge graphs,etc.Social networks[1]trigger the discussion of a lot of hot topics,which leads to a proliferation of highly repetitivedata.Therefore,how to design a graph data compression model is key to effectively storing dense graphs[2].

关键词： quotient graphs structure

Emergence of charge density wave and Ising superconductivity in centrosymmetric monolayer 1T-HfTe_(2)

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Nano Research 2023年第8期16卷 11521-11527页

作者： dawei wang Jizheng Wu Chen Si Department of Medical Engineering Medical Supplies Center of PLA General HospitalBeijing 100853China School of Materials Science and Engineering Beihang UniversityBeijing 100191China

Understanding and control of many-body collective phenomena such as charge density wave(CDW)and superconductivity in atomically thin crystals remains a hot topic in material science.Here,using first-principles calculations,we find that 1T-HfTe_(2)possessing no CDWs in the bulk form,unexpectedly shows a stable 2×2 CDW order in the monolayer form,which can be attributed to the enhancement of electron–phonon coupling(EPC)in the monolayer.Meanwhile,the CDW induces a metal-to-insulator transition in monolayer 1T-HfTe_(2)through the accompanying lattice distortion.Remarkably,Ising superconductivity with a significantly enhanced in-plane critical field can emerge in centrosymmetric monolayer 1T-HfTe_(2)after the CDW is suppressed by electron doping.The Ising paring is revealed to be protected by the spin–orbital locking without the participation of the inversion symmetry breaking which is a must for conventional 2H-NbSe2-like Ising superconductors.Our results open a new window for designing and controlling novel quantum states in two-dimensional(2D)matter.

关键词： charge density wave(CDW) Ising superconductivity two-dimensional(2D)materials HfTe_(2) first-principles calculations

Pan-cancer analysis of DNA methyltransferase family with potential implications in prognosis and immunology in human cancer

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Genes & Diseases 2023年第4期10卷 1206-1209页

作者： Jiayu Ding Hao Shen dawei wang Wenbin Kuang Liping wang Xiao wang Peng Yang State Key Laboratory of Natural Medicines and Jiangsu Key Laboratory of Drug Design and Optimization China Pharmaceutical UniversityNanjingJiangsu 210009China Department of Medicinal Chemistry School of PharmacyChina Pharmaceutical UniversityNanjingJiangsu 211198China

DNA methylation,as a key epigenetic modification affecting gene expression,is catalyzed by DNA methyl-transferase(DNMT).DNMT1,DNMT3A,and DNMT3B are the main members of the DNMT family,which have been found to regulate many biological processes.^(1)Aberrant DNA methylation in the promoter of tumor suppressor genes is considered a biomarker in cancer.However,no evidence of regulatory mechanisms and pathways relating to DNMTs and immune abnormalities has been provided.

关键词： cancer suppressor prognosis

Addressing the impact of canine distemper spreading on an isolated tiger population in northeast Asia

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Integrative Zoology 2023年第6期18卷 994-1008页

作者： dawei wang James L.D.SMITH Francesco ACCATINO Jianping GE Tianming wang Ministry of Education Key Laboratory for Biodiversity Science and Engineering NFGA Key Laboratory for Conservation Ecology of Northeast Tiger and Leopard&College of Life SciencesBeijing Normal UniversityBeijingChina Department of Fisheries Wildlife and Conservation BiologyUniversity of MinnesotaSt.PaulMNUSA UMR SADAPT INRAEAgroParisTechUniversitéParis-SaclayPALAISEAU CedexFrance

The continuation of the isolated Amur tiger(Panthera tigris altaica)population living along the China-Russia border is facing serious challenges due to factors such as its small size(including 38 individuals)and canine distemper virus(CDV).We use a population viability analysis metamodel,which consists of a traditional individual-based demographic model linked to an epidemiological model,to assess options for controlling the impact of negative factors through domestic dog management in protected areas,increasing connectivity to the neighboring large population(including more than 400 individuals),and habitat expansion.Without intervention,under inbreeding depression of 3.14,6.29,and 12.26 lethal equivalents,our metamodel predicted the extinction within 100 years is 64.4%,90.6%,and 99.8%,respectively.In addition,the simulation results showed that dog management or habitat expansion independently will not ensure tiger population viability for the next 100 years,and connectivity to the neighboring population would only keep the population size from rapidly declining.However,when the above three conservation scenarios are combined,even at the highest level of 12.26 lethal equivalents inbreeding depression,population size will not decline and the probability of extinction will be<5.8%.Our findings highlight that protecting the Amur tiger necessitates a multifaceted synergistic effort.Our key management recommendations for this population underline the importance of reducing CDV threats and expanding tiger occupancy to its former range in China,but re-establishing habitat connectivity to the neighboring population is an important long-term objective.

关键词： Amur tiger canine distemper virus habitat connectivity metamodel population viability analysis(PVA)

Hyperextended crustal structure of the Qiongdongnan Basin and subsequent magmatic influence from the Hainan mantle plume

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Science China Earth Sciences 2022年第5期65卷 845-862页

作者： Shaohong XIA Chaoyan FAN dawei wang Jinghe CAO Fang ZHAO Key Laboratory of Ocean and Marginal Sea Geology South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China Sanya Institute of Oceanology SCSIOSanya 572100China Institute of Deep-sea Science and Engineering Chinese Academy of SciencesSanya 572000China

The Qiongdongnan Basin(QDNB)is a rift basin located in the extension direction of the oceanic ridge of the Northwest Subbasin of the South China Sea.This basin is surrounded by Late Cenozoic Ocean Island Basalts(OIBs)magmatism associated with the putative Hainan mantle plume.However,how the Hainan mantle plume has affected the QDNB has not been studied in detail.To reveal the crustal structure of the QDNB and the possible influence of the Hainan mantle plume,we conducted a wide-angle seismic exploration from Hainan Island across the QDNB to the Xisha Block,and obtained the crustal structure by travel-time tomography.The results show that the crustal stretching factors of the Northern and Southern Rises of the QDNB are estimated to be 1.3-2.0,indicating slight or moderate crustal thinning.Whereas,the crustal stretching factor in the Central Depression of the QDNB is estimated to be more than 3.0,which means that the crust has been hyperextended.Controlled by two detachment faults(F2 and F11),the upper and lower crust show brittle and ductile thinning,respectively.Three anomalous low-velocity conduits penetrating the crystalline crust are developed in the Songnan Uplift and the Southern Rise of the QDNB.Their P-wave velocities are 5.5-6.0 km s^(−1),which are significantly lower than those of the surrounding crust(6.0-6.8 km s^(−1)).The Late Cenozoic magmatic intrusions(e.g.,sills and dikes)and hydrothermal activities can be observed in the sedimentary strata above these low-velocity conduits.We interpret that the low-velocity conduits might be the crustal magmatic footprints of the Hainan mantle plume,due to the correlated distributions of OIB-type magmatism,the magmatic intrusion patterns,the deep structure of the Hainan mantle plume and the high heat flow of 95 mW m^(−2).Thus,we propose that the crustal structure of the QDNB is the product of crustal hyperextension in the rifting stage and subsequently affected by the Hainan mantle plume magmatism.This study provides a typical case for understanding the influence

关键词： Crustal structure Hyperextension Magmatism Hainan mantle plume Qiongdongnan Basin

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