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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第9期9卷 1167-1175页

作者： jian-ye zheng An-li WU Guangzhou Metropolis Construction Commission Guangzhou 510030 China College of Civil Engineering and Architecture lnner Mongolia University of Technology Hohhot 010051 China

Mesoscopic characteristics of a clayey soil specimen subjected to macroscopic loading are examined using a medi- cal-use computerized tomography (CT) instrument. Disturbed state concept (DSC) theory is based on the utilization of the hard- ening model. DSC indirectly describes material behavior by claiming that the actual response of the material is expressed in terms of the relative intact (RI) response and the fully adjusted (FA) response. The occurrence of mesoscopic structural changes of material has similarities with the occurrence of a macroscopic response of the material under loadings. In general, the relative changing value of a softening material is three to five times more than that of a hardening material. Whether special zones exist or not in a specimen cross section does not affect the following conclusion: hardening material and softening material show me- chanical differences with CT statistical indices values prominently changing, and the change is related to the superposing of a disturbance factor. A new disturbance factor evolution function is proposed. Thus, mesoscopic statistical indices are introduced to describe macroscopic behavior through the new evolution function. An application of the new evolution function proves the effectiveness of the amalgamation of a macroscopic and a mesoscopic experimental phenomenon measurement methods.

关键词： Constitutive model Disturbed state concept (DSC) Computerized tomography (CT) Softening

Microstructure and high-temperature wear properties of in situ TiC composite coatings by plasma transferred arc surface alloying on gray cast iron

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International Journal of Minerals,Metallurgy and Materials 2015年第12期22卷 1273-1282页

作者： Hang Zhao jian-jun Li zhi-zhen zheng Ai-hua Wang Qi-wen Huang Da-wen Zeng State Key Laboratory of Material Processing and Die & Mould Technology Huazhong University of Science & Technology

In this work, an in situ synthesized TiC-reinforced metal matrix composite （MMC） coating of approximately 350-400μm thickness was fabricated on a gray cast iron （GCI） substrate by plasma transferred arc （PTA） surface alloying of Ti-Fe alloy powder. Microhard- ness tests showed that the surface hardness increased approximately four-fold after the alloying treatment. The microstructure of the MMC coating was mainly composed of residual austenite, acicular martensite, and eutectic ledeburite. Scanning electron microscopy （SEM） and X-ray diffraction analyzes revealed that the in situ TiC particles, which were formed by direct reaction of Ti with carbon originally contained in the GCI, was uniformly distributed at the boundary of residual anstenite in the alloying zone. Pin-on-disc high-temperature wear tests were performed on samples both with and without the MMC coating at room temperature and at elevated temperatures （473 K and 623 K）, and the wear behavior and mechanism were investigated. The results showed that, after the PTA alloying treatment, the wear resistance of the sam- ples improved significantly. On the basis of our analysis of the composite coatings by optical microscopy, SEM with energy-dispersive X-ray spectroscopy, and microhardness measurements, we attributed this improvement of wear resistance to the transformation of the microstruc- ture and to the presence of TiC particles.

关键词： gray cast iron composite coatings particle-reinforced composites titanium carbide surface alloying microstructure wear

Sunspot rotation and magnetic transients associated with flares in NOAAAR 11429

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Research in Astronomy and Astrophysics 2017年第8期17卷 47-56页

作者： jian-Chuan zheng zhi-Liang Yang jian-Peng Guo Kai-Ming Guo Hui Huang Xuan Song Wei-Xing Wan Department of Astronomy Beijing Normal University Beijing 100875 China Key Laboratory of Earth and Planetary Physics Institute of Geology and Geophysics Chinese Academy ofSciences Beijing 100029 China College of Earth Sciences University of Chinese Academy of Sciences Beijing 100049 China

We analyze sunspot rotation and magnetic transients in NOAA AR 11429 during two X-class(X5.4 and X1.3)flares using data from the Helioseismic and Magnetic Imager on board the Solar Dynamics Observatory.A large leading sunspot with positive magnetic polarity rotated *** expected,the rotation was significantly affected by the two *** transients induced by the flares were clearly evident in the sunspots with negative *** were moving across the sunspots with speed of order 3-7 km ***,the trend of magnetic flux evolution in these sunspots exhibited changes associated with the *** results may shed light on understanding the evolution of sunspots.

关键词： sunspots—Sun rotation—Sun magnetic fields

Optimal distributed resource allocation in a wireless sensor network for control systems

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第1期8卷 106-112页

作者： MAO jian-lin WU zhi-ming Department of Automation Shanghai Jiao Tong University Shanghai 200240 China School of Information Engineering and Automation Kunming University of Science and Technology Kunming 650093 China

Wireless technology is applied increasingly in networked control systems. A new form of wireless network called wireless sensor network can bring control systems some advantages, such as flexibility and feasibility of network deployment at low costs, while it also raises some new challenges. First, the communication resources shared by all the control loops are limited. Second, the wireless and multi-hop character of sensor network makes the resources scheduling more difficult. Thus, how to effectively allocate the limited communication resources for those control loops is an important problem. In this paper, this problem is formulated as an optimal sampling frequency assignment problem, where the objective function is to maximize the utility of control systems, subject to channel capacity constraints. Then an iterative distributed algorithm based on local buffer information is proposed. Finally, the simulation results show that the proposed algorithm can effectively allocate the limited communication resource in a distributed way. It can achieve the optimal quality of the control system and adapt to the network load changes.

关键词： Wireless sensor networks (WSN) Distributed resource allocation Control systems Optimization.

A method to study interface diffusion of arsenic into a Nb-Ti microalloyed low carbon steel

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International Journal of Minerals,Metallurgy and Materials 2012年第9期19卷 821-826页

作者： Yuan-zhi Zhu jian-ping XU The Key Laboratory of the Ministry of Education of China for Ferrous Metallurgy and Resources Utilization Wuhan University of Science and Technology Wuhan 430081 China School of Materials and Metallurgy Wuhan University of Science and Technology Wuhan 430081 China

A novel diffusion couple method was used to investigate the interface diffusion of arsenic into a Nb-Ti microalloyed low carbon steel and its effects on phase transformation at the interface. It is discovered that the content of arsenic has great effect on grain growth and phase transformation at high temperature. When the arsenic content is no more than lwt%, there is no obvious grain growth and no obvious ferrite transitional region formed at the diffusion interface. However, when the arsenic content is no less than 5wt%, the grain grows very rapidly. In addition, the arsenic-enriched ferrite transitional layer forms at the diffusion interface in the hot-rolling process, which results from a slower diffusion rate of arsenic atoms than that of carbon in ferrite.

关键词： low carbon steel alloy steel arsenic diffusion bonding phase transformation grain growth

Experimental study on shear behavior of prestressed reactive powder concrete I-girders

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Frontiers of Structural and Civil Engineering 2019年第3期13卷 618-627页

作者： Hui zheng zhi FANG Bin CHEN College of Civil Engineering Hunan University of TechnologyZhuzhou 412007China College of Civil Engineering Hunan UniversityChangsha 410082China

As a new generation of concrete,RPC(Reactive Powder Concrete)has attracted great research attention for its ultra-high strength and high *** the present paper,experimental results from tests on eight prestressed RPC I-section girders failing in shear are reported *** beams with RPC of 120 MPa in compression were designed to assess the ability to carry shear stress in thin webbed prestressed beams with *** test variables were the level of prestressing,shear span-depth ratio(a/d)and stirrup *** deformation,shear capacity and crack pattern were experimentally investigated in *** regard to the shear resistance of the test beams,the predictions from three standards(AFGC,JSCE and SIA)on the design of UHPC structures were compared with the experimental result suggesting that the experimental strength is almost always higher than ***,as a new concrete,was different from normal concrete and fiber reinforced *** study should be needed to develop an analytical method and computation model for shear strength of RPC beams.

关键词： prestressed concrete RPC(Reactive Powder Concrete) concrete beams shear strength experimental study

Nasopharyngeal carcinoma incidence and mortality in China in 2009

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Chinese Journal of Cancer 2013年第8期32卷 453-460页

作者： zhi-jian Xu Rong-Shou zheng Si-Wei Zhang Xiao-Nong Zou Wan-Qing Chen Cancer Screening Center Cancer Hospital Chinese Academy of Medical Sciences National Office for Cancer Prevention and Control & National Cancer Center

Nasopharyngeal carcinoma (NPC) is rare globally but common in China and exhibits a distinct ethnic and geographic distribution. In 2009, the National Central Cancer Registry in China provided real-time surveillance information on NPC. Individual NPC cases were retrieved from the national database based on the ICD-10 topography code C11. The crude incidence and mortality of NPC were calculated by sex and location (urban/rural). China's population in 1982 and Segi's world population structures were used to determine age-standardized rates. In regions covered by the cancer registries in 2009, the crude incidence of NPC was 3.61/100,000 (5.08/100,000 in males and 2.10/100,000 in females; 4.19/100,000 in urban areas and 2.42/100,000 in rural areas). Age-standardized incidences by Chinese population (ASIC) and Segi's world population (ASIW) were 2.05/100,000 and 2.54/100,000, respectively. The crude mortality of NPC was 1.99/100,000 (2.82/100,000 in males and 1.14/100,000 in females; 2.30/100,000 in urban areas and 1.37/100,000 in rural areas). The age-standardized mortalities by Chinese population (ASMC) and world population (ASMW) were 1.04/100,000 and 1.35/100,000, respectively. The incidence and mortality of NPC were higher in males than in females and higher in urban areas than in rural areas. Both agespecific incidence and mortality were relatively low in persons younger than 30 years old, but these rates dramatically increased. Incidence peaked in the 60-64 age group and mortality peaked in the over 85 age group. Primary and secondary prevention, such as lifestyle changes and early detection, should be carried out in males and females older than 30 years of age.

关键词：中国人口死亡率发病率鼻咽癌全国人民代表大会农村地区世界人口年龄组

A Search Technique Based on Deep Learning for Fast Radio Bursts and Initial Results for FRB 20201124A with the NSRT

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Research in Astronomy and Astrophysics 2022年第10期22卷 77-85页

作者： Yan-Ling Liu jian Li zhi-Yong Liu Mao-zheng Chen jian-Ping Yuan Na Wang Rai Yuen Hao Yan Xinjiang Astronomical observatory Chinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Radio Astronomy Chinese Academy of SciencesNanjing 210033China Xinjiang Key Laboratory of Microwave Technology Urumqi 830011China

The origin and phenomenology of Fast Radio Bursts(FRBs) remain unknown. Fast and efficient search technology for FRBs is critical for triggering immediate multi-wavelength follow-up and voltage data dump. This paper proposes a dispersed dynamic spectra search(DDSS) pipeline for FRB searching based on deep learning, which performs the search directly from observational raw data, rather than relying on generated FRB candidates from single-pulse search algorithms that are based on de-dispersion. We train our deep learning network model using simulated FRBs as positive and negative samples extracted from the observational data of the Nanshan 26 m radio telescope(NSRT)at Xinjiang Astronomical Observatory. The observational data of PSR J1935+1616 are fed into the pipeline to verify the validity and performance of the pipeline. Results of the experiment show that our pipeline can efficiently search single-pulse events with a precision above 99.6%, which satisfies the desired precision for selective voltage data dump. In March 2022, we successfully detected the FRBs emanating from the repeating case of FRB 20201124A with the DDSS pipeline in L-band observations using the NSRT. The DDSS pipeline shows excellent sensitivity in identifying weak single pulses, and its high precision greatly reduces the need for manual review.

关键词： radio continuum general-methods data analysis-methods observational

Stem cell therapy: A promising treatment for COVID-19

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World Journal of Clinical Cases 2021年第36期9卷 11148-11155页

作者： zhi-Xue zheng Department of General Surgery Beijing Jishuitan HospitalBeijing 100035China

Novel coronavirus disease 2019(COVID-19)caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)has become a global ***-2 is an RNA virus and has a glycosylated spike(S)protein used for genome ***-19 can lead to a cytokine storm and patients usually have early respiratory signs and further secondary infections,which can be ***-19 has entered an emergency phase,but there are still no specific effective drugs for this *** stem cells(MSCs)are multipotent stromal cells,which cause antiapoptosis and can repair damaged epithelial *** clinical trials have proved that MSC therapy could be a potential feasible therapy for COVID-19 patients,especially those with acute respiratory distress syndrome,without serious adverse events or ***,more studies are needed in the future,in order to confirm the effect of this therapy.

关键词： COVID-19 SARS-CoV-2 Mesenchymal stem cells Pandemic Stem cell therapy

Glucose alleviates cadmium toxicity by increasing cadmium fi xation in root cell wall and sequestration into vacuole in Arabidopsis

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Journal of Integrative Plant Biology 2015年第10期57卷 830-837页

作者： Yuan-zhi Shi Xiao-Fang Zhu jiang-Xue Wan Gui-Xin Li Shao-jian zheng Tea Research Institute of the Chinese Academy of Agricultural Sciences and the Key Laboratory for Plant Biology and Resource Application of Tea the Ministry of Agriculture State Key Laboratory of Plant Physiology and Biochemistry College of Life SciencesZhejiang University State Key Laboratory of Soil and Sustainable Agriculture China Institute of Soil Science the Chinese Academy of Science College of Agronomy and Biotechnology Zhejiang University

Glucose (Glu) is involved in not only plant physiological and developmental events but also plant responses to abiotic stresses. Here, we found that the exogenous Glu improved root and shoot growth, reduced shoot cadmium (Cd) concentration, and rescued Cd-induced chlorosis in Arabidopsis thaliana (Columbia ecotype, Col-0) under Cd stressed conditions. Glucose increased Cd retained in the roots, thus reducing its translocation from root to shoot significantly. The most Cd retained in the roots was found in the hemicellulose 1. Glucose combined with Cd (Glu t Cd) treatment did not affect the content of pectin and its binding capacity of Cd while it increased the content of hemicelluloses 1 and the amount of Cd retained in it significantly. Furthermore, Leadmium Green staining indicated that more Cd was compartmented into vacuoles in Glu t Cd treatment compared with Cd treatment alone, which was in accordance with the significant upregulation of the expression of tonoplast-localized metal transporter genes, suggesting that com-partmentation of Cd into vacuoles also contributes to the Glu-alleviated Cd toxicity. Taken together, we demonstrated that Glu-alleviated Cd toxicity is mediated through increas-ing Cd fixation in the root cell wall and sequestration into the vacuoles.

关键词： Arabidopsis cadmium tolerance glucose plant cell wall plant vacuole