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Inherent relationship between process parameters,crystallization and mechanical properties of continuous carbon fiber reinforced PEEK composites

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Defence Technology（防务技术） 2023年第6期24卷 269-284页

作者： Xiao-long Ma li-hua wen Shi-yu Wang Jin-you Xiao wen-hao li Xiao Hou School of Astronautics Northwestern Polytechnical UniversityXi'an710072China China Aerospace Science and Technology Corporation Beijing100048China

High-performance thermoplastic composites have been developed as significant structural materials for cutting-edge equipment in the aerospace and defence ***,the internal mechanism of processing parameters on mechanical properties in the manufacturing process of thermoplastic composite structures is still a serious *** purpose of this study is to investigate the process/crystallization/property relationships for continuous carbon fiber(CF)reinforced polyether-ether-ketone(PEEK)*** composite laminates are fabricated according to orthogonal experiments via the thermoforming *** mechanical performance is investigated in terms of crystallization properties and fracture morphology *** results show that the mechanical performance and crystallization properties of thermoplastic composites are significantly affected by the coupling of processing *** increased molding temperature,pressure,and holding time improve the degree of fiber/matrix infiltration and affect the crystallinity and crystalline morphology of the matrix,which further influences the mechanical properties of the *** is reflected in the test results that crystallinity has an approximately linear effect on mode-I interlaminar fracture toughness and transverse flexural *** well as the higher molding temperature can destroy the pre-existent crystals to improve the toughness of the matrix,and the well-defined crystalline structures can be observed when fabricated at higher temperatures and longer periods of holding time.

关键词： Polymer matrix composites Thermoplastic Processing parameters Mechanical properties Crystallization

Quantum Signatures of Chaos in Adiabatic Interaction Between a Trapped Ion and a Laser Standing Wave

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Communications in Theoretical Physics 2008年第1期49卷 143-152页

作者： li Hui HAI wen-hua XU Jun Department of Physics Hunan Normal University Changsha 410081 China

We study quantum motion around a classical heteroclinic point of a single trapped ion interacting with a strong laser standing wave. We construct a set of exact coherent states of the quantum system and from the exact solutions reveal that quantum signatures of chaos can be induced by the adiabatic interaction between the trapped ion and the laser standing wave, where the quantum expectation values of position and momentum correspond to the classically chaotic orbit. The chaotic region on the phase space is illustrated. The energy crossing and quantum resonance in time evolution and the exponentially increased Heisenberg uncertainty are found. The results suggest a theoretical scheme for controlling the unstable regular and chaotic motions.

关键词： quantum chaos stability adiabatic evolution level crossing quantum resonance control

Overexpression of a Chloroplast-located Peroxiredoxin Q Gene, SsPrxQ, Increases the Salt and Low-temperature Tolerance of Arabidopsis

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Journal of Integrative Plant Biology 2006年第10期48卷 1244-1249页

作者： li-wen Jing Shi-hua Chen Xiao-li Guo Hui Zhang Yan-Xiu Zhao Key Laboratory of Plant Stress Research College of Life Sciences Shandong Normal University Jinan 250014 China

Ablotlc stress, such as salt, drought and extreme temperature, can result in enhanced production of reactive oxygen species （ROS）. Plants have developed both enzymatic ROS-scavenging and non-enzymatic ROS-scavenging systems. The major ROS-scavenging enzymes of plants include superoxide dismutase （SOD）, ascorbate peroxldaae （APX）, catalaae （CAT）, glutathione peroxldaae （GPX） and peroxiredoxina （Prxa）. In the present work, we identified a gene encoding chloroplast-located peroxiredoxin Q, SsPrxQ, from Suaeda salsa L. located at chloroplast. Overexpression of SsPrxQ In Arabidopsis leads to an increase In salt and low-temperature tolerance.

关键词： overexpression peroxiredoxin Q salt and low-temperature tolerance suaeda salsa subcellular localization

Oncological outcome of unresectable lung metastases without extrapulmonary metastases in colorectal cancer

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World Journal of Gastroenterology 2010年第26期16卷 3318-3324页

作者： li, wen-hua Peng, Jun-Jie Xiang, Jia-Qing Chen, Wei Cai, San-Jun Zhang, wen Fudan Univ Shanghai Canc Ctr Dept Med Oncol Shanghai 200032 Peoples R China Fudan Univ Shanghai Canc Ctr Dept Colorectal Surg Shanghai 200032 Peoples R China Fudan Univ Shanghai Canc Ctr Dept Thorac Surg Shanghai 200032 Peoples R China Univ Michigan Dept Biostat Ann Arbor MI 48710 USA

AIM: To explore the oncological outcomes of unresectable lung metastases without extrapulmonary metastases in colorectal cancer. METHODS: Patients with unresectable isolated lung metastases from colorectal cancer were prospectively collected in a single institution during a 5-year period. All patients received either the fluorouracil/leucovorin plus oxaliplatin, fluorouracil/leucovorin plus irinotecan or capecitabine plus oxaliplatin regimen as first-line treatment. The resectability after preoperative chemotherapy was evaluated. Patients' outcome and predictive factors for overall survival were also investigated by univariate and multivariate ***: A total of 70 patients were included in the study. After standardized fi rst-line chemotherapy, only 4 patients (5.7%) were converted to resectable disease. The median overall survival time in all patients was 19 mo (95% CI: 12.6-25.4), with a 2-year overall survival rate of 38.8%. No survival difference was found among different fi rst-line chemotherapeutic regimens. Prognostic analysis demonstrated that only the fi rst response assessment for fi rst-line treatment was the independent factor for predicting overall survival. The median survival time in partial response, stable disease and progressive disease patients were 27 mo, 16 mo and 8 mo (P = 0.00001). CONCLUSION: Pulmonary metastasectomy can only be performed in a small part of unresectable lung metastases patients after chemotherapy. Patients' first response assessment is an important prognostic factor.

关键词： Colorectal cancer Lung Metastases Chemotherapy

Micro-vibration Modeling and Verification of Shutter Mechanism of Survey Space Telescope

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Research in Astronomy and Astrophysics 2023年第1期23卷 242-253页

作者： Tong-Lei Jiang li-hua wen Hu Zhan Bo Wang Yong-Chao Yang School of Astronautics Northwestern Polytechnical UniversityXi’an 710072China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China

The scientific research mission of the Survey Space Telescope(also known as the China Space Station Telescope,CSST)imposes rigorous requirements on the observation ***,microvibrations generated by the shutter mechanism can seriously affect the performance of the highly precise and sensitive instruments *** study presents a dynamic model and verifies its performance using experimental ***,a five-degreeof-freedom nonlinear dynamic model that considers all interference sources and bearing nonlinearity is *** validity of the proposed model is verified using experimental measurements of the microvibration *** obtained results proved that the proposed dynamic model can accurately predict the characteristics of the microvibrations caused by the shutter mechanism in the design stage and provide a theoretical basis for the development of CSST.

关键词： telescopes-surveys-methods numerical-methods analytical

Influence of ginseng cultivation under larch plantations on plant diversity and soil properties in liaoning Province,Northeast China

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Journal of Mountain Science 2016年第9期13卷 1598-1608页

作者： liU Wei-wei liU Mou-cheng li wen-hua ZENG Fan-shun QU Yi Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China liaoning Academy of Forestry Shenyang 110032China

Currently, transforming the mode of forest management and developing multiple forest management practices are actively encouraged in China. As one forest management type, ginseng cultivation under larch plantations has been developed significantly in the east of liaoning Province. However, research on the influence of the ecological environment for this mode of production is still deficient. Based on this, our study compares the plant diversity and soil properties in the ginseng cultivation under larch plantations(LG) with larch plantations(LP) and natural secondary forests(SF). First, we randomly selected three plots for each of the three stand types which have similar stand characteristics; then, we carried out a plant diversity survey and soil sampling in each of the nine plots. The results show that no significant difference was found in plant diversity between LG and LP, but theevenness of herbs was significantly lower in LG than LP. No obvious changes in soil physical properties were found in LG, but a significant decrease in most of the soil nutrient content was presented in LG. Furthermore, we found a correlation between plant diversity(H') and soil properties in the three kinds of stand types, especially between herbaceous plant diversity and soil properties. We conclude that ginseng cultivation under larch plantations has no obvious effect on plant diversity, except the herbaceous evenness. Soil fertility can be depleted significantly in LG, but physical structures are not affected. Moreover, maintaining the diversity of herbaceous plants and controlling the density of ginseng cultivation in LG by farmers are important for the ecological environment. Based on this study and its good comprehensive benefits and with the support of policy, we think this forest management type should be promoted moderately in the region.

关键词： Forest management Ginseng cultivation Larch plantations Secondary forests Plant diversity Soil properties Changbai Mountain

Relationship between hyperuricemia and metabolic syndrome

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2007年第8期8卷 593-598页

作者： CHEN li-ying ZHU wen-hua CHEN Zhou-wen DAI Hong-lei REN Jing-jing CHEN Jian-hua CHEN Lei-qian FANG li-zheng Department of Family Medicine Sir Run Run Shaw Hospital School of Medicine Zhejiang University Hangzhou 310016 China

Objective: To investigate the relationship between metabolic syndrome and hyperuricemia. Methods: A total of 2 374 subjects who received health examination in our hospital from Jan. 2004 to Dec. 2006 were enrolled in our study. Hyperuricemia is defined as ≥7 mg/dl (in men) or ≥6.0 mg/dl (in women). Metabolic syndrome was defined using AHA/NHLBI (American Heart Association/National Heart, Lung, and Blood Institute) criteria. Results: (1) The overall prevalence of hyperuricemia was 13.10%. The condition was more common in men than in women (19.07% vs 3.42%). (2) Among men, uric acid concentration is statistically significantly positively correlated with waist circumference, blood pressure, and triglyceride. Uric acid is negatively correlated with serum high-density lipoprotein-cholesterol (HDL-C). Uric acid concentration is most strongly correlated with serum triglyceride (r=0.379) and waist circumference (r=0.297). Among women, statistically significant positive correlations were noted for the serum uric acid concentrations with waist circumference, triglyceride and fasting plasma glucose. Serum triglyceride (r=0.329) and waist circumference (r=0.234) are most strongly correlated with uric acid concentrations. (3) Men with hyperuricemia had a 1.634-fold increased risk of metabolic syndrome as compared with those without hyperuricemia odds ratio (OR)=1.634, P=0.000. Women with hyperuricemia had a 1.626-fold increased risk of metabolic syndrome (OR=1.626, P=0.000) as compared with those without hyperuricemia. Conclusion: Hyperuricemia is prevalent among Chinese population. Additionally, serum uric acid is positively associated with metabolic syndrome.

关键词： Hyperuricemia Metabolic syndrome Triglyceride

Construction and Resource Locating of Semantic P2P Grid Based on Description Logics

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Wuhan University Journal of Natural Sciences 2006年第1期11卷 78-82页

作者： SUN Xiao-lin LU Zheng-ding li Yu-hua wen Kun-mei li Rui-xuan College of Computer Science and Technology HuazhongUniversity of Science and Technology Wuhan 430074Hubei China

This paper proposes an algorithm applied in se mantic P2P network based on the description logics with the purpose for realizing the concepts distribution of resources, which makes the resources semantic locating easy. With the idea of the consistent hashing in the Chord, our algorithm stores the addresses and resources with the values of the same type to select instance. In addition, each peer has its own ontology, which will be completed by the knowledge distributed over the network during the exchange of CHGs （classification hierarchy graphs）. The hierarchy classification of concepts allows to find matching resource by querying to the upper level concept because the all concepts described in the CHG have the same root.

关键词： semantic P2P description logics consistent hashing ontology CHG (classification hierarchy graphs)

Effect of respiratory syncytial virus on the activity of matrix metalloproteinase in mice

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Chinese Medical Journal 2007年第1期120卷 5-11页

作者： li wen SHEN hua-hao Department of Respiratory Medicine Second Affiliated HospitalZhejiang University College of Medicine Institute of RespiratoryDiseases Zhejiang University Hangzhou 310009 China

Background Respiratory syncytial virus （RSV） is a common pathogen in the lower respiratory tract of infants and children. Recent studies have shown that in adults, especially in the eldedy population who have relatively weak immunity, lower respiratory tract infection is not uncommon. RSV was detected in 22% hospitalized patients with acute exacerbation of chronic obstructive pulmonary disease （COPD）, and the detection rate was only next to that of parvovirus and influenza virus respectively. Further studies revealed that lung infection of RSV could lead to inflammatory destruction and structural remodeling. This study was undertaken to examine the effect of infection with RSV on matrix metalloproteinase （MMPs） in mice, and to explore the role of RSV in the pathogenesis of pulmonary diseases. Methods Twenty BALB/c mice were divided randomly into an RSV infection group and a blank control group. The mice in the RSV infection group were given 100 pl liquid containing 10s PFU of RSV by intranasal instillation. Three days after the infection, the bronchoalveolar lavage fluid （BALF） was harvested and RT-PCR and Western blotting were used to detect MMP-9 and the expression of tissue inhibitors of matdx metalloproteinase （TIMP）-I mRNA in lung tissues. Gelatin zymography was employed to detect the activities of MMP-9 and MMP-2 in BALF. Immunohistochemistry was used to determine the expressions of E-cadherin （E-cd） and proliferating call nuclear antigen （PCNA） in the lung tissues. Results In the BALF of the mice infected with RSV, the activities of MMP-9 and MMP-2 were significantly increased （t=-6.08, P〈0.01 and t=5.68, P〈0.01）. The levels of mRNAand proteins of MMP-9 in the lung tissues of the mica infected with RSV were significantly elevated, and the mRNA and protein levels were significantly higher than those of the blank controls. Though the ratio of MMP-9/TIMP-1 mRNA in the lung tissues of the infected mica was not significantly different from that of the normal c

关键词： respiratory syncytial virus matrix metalloproteinase inhibitory agents E-caherin,. proliferating cell nuclear antigen