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Partially coherent vortex beams:Fundamentals and applications

Science China(Physics,Mechanics & Astronomy) 2021年第2期64卷 32-50页

作者： Miao dong ChengLiang Zhao YangJian cai YuanJie Yang School of Physics University of Electronic Science and Technology of ChinaChengdu611731China School of Physical Science and Technology Soochow UniversitySuzhou215006China Shandong Provincial Engineering and Technical Centre of Light Manipulations&Shandong Provincial Key Laboratory of Optics and Photonic Device School of Physics and ElectronicsShandong Normal UniversityJinan250014China

It has been over 30 years since the concept of optical vortices was first proposed by Coullet et *** 1989,and the field of structured beams has grown *** the last two decades,partially coherent vortex beams(PCVBs)have received increasing interest in the fields of optical manipulation,optical communication,optical imaging,etc.,and great progress has been made in the area of the coherence singularities,generation methods,topological charge measurements,and promising applications of *** this review,we firstly outline the basic concepts of *** explicate the relationship between the coherence vortices and optical vortices,and the evolution behavior of optical vortices to coherence vortices is summarized in *** discuss a special form of coherence singularity,ring dislocation,mathematically and *** ring dislocation in the correlation functions under low coherence is dependent on the mode indices,which provide a feasible approach to measure mode indices of ***,we summarize the various methods for measuring the topological charge of PCVBs,highlight the measurement method based on the cross-correlation function,and a physical explanation on the relation between ring dislocation and topological charge is *** that,we review the recent advances on experimental generation of several kinds of ***,we give an overview on the potential applications of PCVBs.

关键词： coherence singularities coherence vortices vortex beams topological charge

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Structural bonding-breakage constitutive model for natural unsaturated clayey soils

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Acta Mechanica Sinica 2010年第6期26卷 931-939页

作者： Guo-qing cai Cheng-Gang Zhao Xiao-Ming Qin Department of Geotechnique.School of Civil Engineering and Architecture Beijing Jiaotong University Beijing 100044China Hydro China Zhongnan Engineering Corporation Changsha 410014China

The natural clayey soils are usually structural and unsaturated,which makes their mechanical properties quite different from the remolded saturated soils.A structural constitutive model is proposed to simulate the bonding-breakage *** this model,the unsaturated soil element is divided into a cementation element and a friction element according to the binary medium theory,and the stress-strain coordination for these two elements is obtained. The cementation element is regarded as elastic,whereas the friction element is regarded as elastoplastic which can be described with the Gallipoli＇s *** theoretical formulation is verified with the comparative experiments of isotropic compressions on the saturated and unsaturated structural *** analyses of the effects of damage variables on the model predictions are further carried out,which show that breakage deformation of natural clayey soils increases with the rising amount of initial defects.

关键词： Unsaturated clayey soils Structure Micro-mechanism of bonding-breakage Constitutive model

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Chlorobenzenes in waterweeds from the Xijiang River (Guangdong section) of the Pearl River

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Journal of Environmental Sciences 2007年第10期19卷 1171-1177页

作者： DU qing-ping JIA Xiao-shan HUANG cai-na Faculty of Environmental Science and Engineering Guangdong University of Technology Guangzhou 510006 China School of Environmental Science and Engineering Sun Yat-sen University Guangzhou 510275 China

The Xijiang River is the major source of water for about 4.5 millions of urban population and 28.7 millions of rural population. The water quality is very important for the health of the rural population. The concentration and distribution of chlorobenzenes （CBs） in both water and waterweeds collected from 4 stations in the Xijiang River （Gangdong section） of the Pearl River in April and November were determined. The result showed that nearly every congener of CBs was detected. The total contents of CBs （ZCBs） in the river water ranged from 111.1 to 360.0 ng/L in April and from 151.9 to 481.7 ng/L in November, respectively. The pollution level of CBs in the water in April was higher than that in November. The contents of ZCBs in waterweeds ranged from 13.53×10^2μg/g to 38.27×10^2μg/g dry weight （dw）. There was no significant difference between April and November in waterweeds. The distribution of CBs in roots, caulis, and leaves of Vallisneria spiralis L. showed different patterns. The leaves mainly contained low-molecular-weight CBs （DCBs）, whereas the roots accumulated more PCBs and HCBs. The average lgBCFlip （bioconcentration factor） of CBs ranged from 0.64 to 3.57 in the waterweeds. The spatial distribution character of CBs in the Xijiang River was： Fengkai County 〈 Yunan County 〈 Yun＇an County 〈 Gaoyao County according to the ZCBs, and the pollution deteriorated from the upstream to the downstream of the Xijiang River. Further analysis demonstrated that the discharge of waste containing CBs may be the main source of CBs pollution in the Xijiang River .

关键词： chlorobenzenes pollution water water weeds distribution bioconcentration factor

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Influence of reaction piles on test pile response in a static load test

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2013年第3期14卷 198-205页

作者： Qian-qing ZHANG Shu-cai LI Zhong-miao ZHANG Geotechnical and Structural Engineering Research Center Shandong University MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering Zhejiang University

This work presents a new analytical method to analyze the influence of reaction piles on the test pile response in a static load *** our method,the interactive effect between soil and pile is simulated using independent springs and the shear displacement method is adopted to analyze the influence of reaction piles on test pile ***,the influence of the sheltering effect between reaction piles and test pile on the test pile response is taken into *** cases are analyzed to verify the rationality and efficiency of the present *** method can be easily extended to a nonlinear response of an influenced test pile embedded in a multilayered soil,and the validity is also demonstrated using centrifuge model tests and a computer program presented in the *** present analyses indicate that the proposed method will lead to an underestimation of the test pile settlement in a static load test if the influence of the presence of reaction piles on the test pile response is neglected.

关键词： Test pile Reaction pile Shear displacement method Sheltering effect Multilayered soil

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Molecular mapping of stripe rust resistance gene YrH9017 in wheat-Psathyrostachys huashanica introgression line H9017-14-16-5-3

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Journal of Integrative Agriculture 2019年第1期18卷 108-114页

作者： MA dong-fang HOU Lu SUN cai ZHANG Xing YIN Jun-liang GUO qing-yun ZHU Yong-xing qinghai Academy of Agriculture and Forestry Sciences Qinghai University/Key Laboratory of Agricultural Integrated Pest ManagementQinghai Province/State Key Laboratory of Plateau Ecology and AgricultureQinghai University Hubei Collaborative Innocvtion Center for Grain Industry/College of Agriculture Yangtze University

Several new stripe rust pathogen races emerged in the wheat growing regions of China in recent *** races were virulent to most of the designated wheat seedling resistance ***,it is necessary and worthwhile to identify new valuable resistant materials for the sake of diversifying resistant sources,pyramiding different resistance genes and achieving durable ***,we identified the resistance gene,temporarily designated as YrH9017,in wheat-Psathyrostachys huashanica introgression line H9017-14-16-5-3.A total of 146 F2 plants and their derived F2:3 families in a cross of Mingxian 169 and H9017-14-16-5-3 were used to evaluate seedling stripe rust response and as a mapping ***,we constructed a genetic map including eight simple sequence repeat(SSR) markers and expressed sequence tag(EST) ***9017 was located on the long arm of chromosome 2A and closely linked with two EST-sequence tagged site(EST-STS) markers BG604577 and BE471201 at 1.3 and 1.8 cM distance,*** two closest markers could be used for marker-assisted selection of YrH9017 in breeding.

关键词： Puccinia striiformis Psathyrostachys huashanica stripe rust molecular mapping resistance gene

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Effect of reduction pretreatment process on evolution of micro-porosity in 42CrMo billet

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Journal of Iron and Steel Research International 2021年第4期28卷 413-423页

作者： Zhen Ning Wei Yu Hong-qiang Liu qing-wu cai Collaborative Innovation Centre of Steel Technology University of Science and Technology BeijingBeijing 100083China HBIS Group Co. Ltd.Shijiazhuang 050000HebeiChina

Reduction pretreatment(RP)process,which is implemented after the billet is completely solidified,is an alternative process to further improve billet *** element method and experiment were used to investigate the effect of the RP process on the internal quality of 42CrMo *** ultrasonic testing technology was used to study the influence of the RP process on the *** a three-dimensional finite element model,the mechanism of the RP process on the porosity closure was *** experimental results show that the RP process eliminates the macro-porosities of the billet *** number of micro-porosities in the billets is effectively reduced,and the increase in deformation contributes to the reduction in *** with isothermal rolling,the RP process leads to a larger equivalent strain and hydrostatic integration in the billet center because of the temperature gradient,and the effect of the temperature gradient is greater with the increase in *** closure effect of micro-porosity is related not only to the stress state,but also to the distribution of *** increase in three-dimensional compressive stress is beneficial to the porosity *** the micro-porosities distributed densely,excessive stress could induce micro-porosity coalescence,which has the risk of inducing cracks.

关键词： Reduction pretreatment Temperature gradient Large deformation Micro-porosity Ultrasonic testing

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Impacts of chemical fertilizer reduction and organic amendments supplementation on soil nutrient,enzyme activity and heavy metal content

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Journal of Integrative Agriculture 2017年第8期16卷 1819-1831页

作者： NING Chuan-chuan GAO Peng-dong WANG Bing-qing LIN Wei-peng JIANG Ni-hao cai Kun-zheng Key Laboratory of Tropical Agro-environment Ministry of Agriculture/South China Agricultural UniversityGuangzhou 510642P.R.China

Excessive use of agro-chemicals （such as mineral fertilizers） poses potential risks to soil quality. Application of organic amendments and reduction of inorganic fertilizer are economically feasible and environmentally sound approaches to de- velop sustainable agriculture. This study investigated and evaluated the effects of mineral fertilizer reduction and partial substitution of organic amendment on soil fertility and heavy metal content in a 10-season continually planted vegetable field during 2009-2012. The experiment included four treatments： 100% chemical fertilizer （CF100）, 80% chemical fertilizer （CF80）, 60% chemical fertilizer and 20% organic fertilizer （CF60＋OM20）, and 40% chemical fertilizer and 40% organic fertilizer （CF40＋OM40）. Soil nutrients, enzyme activity and heavy metal content were determined. The results showed that single chemical fertilizer reduction （CF80） had no significant effect on soil organic matter content, soil catalase activity and soil heavy metal content, but slightly reduced soil available N, P, K, and soil urease activity, and significantly reduced soil acid phosphatase activity. Compared with CF100, 40 or 60% reduction of chemical fertilizer supplemented with organic fertilizer （CF60＋OM20, CF40＋OM40） significantly increased soil organic matter, soil catalase activity and urease activity especially in last several seasons, but reduced soil available P, K, and soil acid phosphatase activity. In addition, continu- ous application of organic fertilizer resulted in higher accumulation of Zn, Cd, and Cr in soil in the late stage of experiment, which may induce adverse effects on soil health and food safety.

关键词： chemical fertilizer organic amendments soil fertility vegetable soil health heavy metal

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Oxidation damage and interfacial failure of dissimilar metal welds containing ferritic heat resistant steels

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Journal of Iron and Steel Research International 2021年第11期28卷 1439-1450页

作者： Xiao-gang Li Zhi-peng cai Xin Chen Shu-qing dong Wen-he cai Yu Zhang Shan-lin Li Ke-jian Li Shao-shi Rui Ji-luan Pan Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China Key Laboratory for Advanced Materials Processing Technology Ministry of EducationBeijing 100084China State Key Laboratory of Tribology Tsinghua UniversityBeijing 100084China Collaborative Innovation Center of Advanced Nuclear Energy Technology Tsinghua UniversityBeijing 100084China China Datang Corporation Science and Technological Research Institute Thermal Power Technology Research InstituteBeijing 100040China

The ex-service steam tubes containing dissimilar metal weld(DMW)between high Cr ferritic steel T91 and austenitic stainless steel TP347H and the ex-service steam tubes containing DMW between low Cr ferritic steel G102 and austenitic stainless steel TP347H were obtained from coal-fired thermal power plants in China,and their microstructures at the nickel-based weld metal(WM)/ferritic steel interfaces and oxidation characteristics were *** operating for 15,000 h at steam temperature of 541 C and steam pressure of 17.5 MPa,a G102/TP347H DMW failed along the WM/G102 steel interface,which was a dangerous premature failure mode without obvious plastic *** interfacial failure was attributed to the interaction between oxidation and cracking along the interface,where fracture appeared to be related with the strain concentration at the *** notch along the WM/G102 steel interface was the precursor of premature interfacial failure of DMW involving *** the DMW involving high Cr ferritic steel T91,ferritic steel side could form a Cr-rich passive film during service and thus would not be further oxidized after operating for 67,000 h at steam temperature of 541 C and steam pressure of 3.5 *** was concluded that oxidation played a more important role in failure of these DMWs,and retarding the development of oxidation and avoiding the interfacial oxide notch would dramatically improve the service performance of steam tubes containing DMWs.

关键词： Dissimilar metal weld Ferritic heat resistant steel Nickel-based weld metal Oxidation Interfacial failure High-temperature service

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Effects of moisture and carbonate additions on CO_2 emission from calcareous soil during closed–jar incubation

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Journal of Arid Land 2014年第1期6卷 37-43页

作者： YanJie dong Miao cai JianBin ZHOU College of Natural Resources and Environment Northwest A&F University Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China Ministry of Agriculture

Calcareous soil contains organic and inorganic carbon(C) pools,which both contribute to CO2 emission during closed-jar incubation. The mineralization of organic C and dissolution of inorganic C are both related to soil moisture,but the exact effect of water content on CO2 emission from calcareous soil is unclear. The objective of this experiment was to determine the effect of soil water content(air-dried,30%,70%,and 100% water-holding capacity(WHC)),carbonate type(CaCO3 or MgCO3),and carbonate amount(0.0,1.0%,and 2.0%) on CO2 emission from calcareous soil during closed-jar incubation. Soil CO2 emission increased significantly as the water content increased to 70% WHC,regardless of whether or not the soil was amended with carbonates. Soil CO2 emission remained the same or increased slowly as the soil water content increased from 70% WHC to 100% WHC. When the water content was ≤30% WHC,soil CO2 emission from soil amended with 1.0% inorganic C was greater than that from unamended soil. When the soil water content was 70% or 100% WHC,CO2 emission from CaCO3 amended soil was greater than that from the control. Furthermore,CO2 emission from soil amended with 2.0% CaCO3 was greater than that from soil amended with 1.0% CaCO3. Soil CO2 emission was higher in the MgCO3 amended soil than from the unamended soil. Soil CO2 emission decreased as the MgCO3 content increased. Cumulative CO2 emission was 3-6 times higher from MgCO3 amended soil than from CaCO3 amended soil. There was significant interaction effect between soil moisture and carbonates on CO2 emission. Soil moisture plays an important role in CO2 emission from calcareous soil because it affects both biotic and abiotic processes during the closed-jar incubation.

关键词： calcareous soil soil moisture organic carbon CO2 emission

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A Light Weight Traffic Volume Prediction Approach Based on Finite Traffic Volume Data

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Journal of Systems Science and Systems Engineering 2023年第5期32卷 603-622页

作者： Xing Su Minghui Fan Zhi cai qing Liu Xiaojun Zhang Faculty of Information Technology Bering University of TechnologyBeijing100124China Shanghai Ocean University Shanghai201306China Academy of Opto-electronics Chinese Academy of SciencesBeijing100094China

As one of the key technologies of intelligent transportation systems, short-term traffic volume prediction plays an increasingly important role in solving urban traffic problems. In the last decade, many approaches were proposed for the traffic volume prediction from different perspectives. However, most of these approaches are based on a large amount of historical data. When there are only finite collected traffic data, they cannot be well trained, so the prediction accuracy of these approaches will be poor. In this paper, a tensor model is proposed to capture the change patterns of continuous traffic volumes. From collected traffic volume data, the element data are extracted to update the corresponding elements of the tensor model. Then, a tucker decomposition and gradient descent based algorithm is employed to impute the missing elements of the tensor model. After missing element imputation, the tensor model can be directly applied to the short-term traffic volume prediction through searching the corresponding elements of the model and the storage cost of the model is low. Our model is evaluated on real traffic volume data from PeMS dataset, which indicates that our model has higher traffic volume prediction accuracy than other approaches in the situation of finite traffic volume data.

关键词： Short-term traffic volume prediction tensor Tucker decomposition finite traffic volume data

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