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Journal of Environmental Sciences 2017年第5期29卷 206-213页

作者： Guangke Li Junyan Chen Wei yan nan Sang College of Environment and Resource Shanxi University Taiyuan 030006 China

To compare the toxicity of landfill leachate exposure at the early stages of seed soaking and germination on maize,a field experiment was conducted to evaluate the physiological aspects of growth,yield and potential clastogenicity of root-tip cells. The maizes were treated with leachate at levels of 2%,10%,20%,30% or 50%（V/V）. First,the change of physiological indexes,including chlorophyll（Chl）,Malondialdehyde（MDA）and Reactive oxygen species（ROS）levels,combined with yield all showed that soaking with leachate,but not germination,generated a greater ecological risk on maize. After a soaking treatment of maize with 50% leachate,the Chl,MDA and ROS levels during a vigorous growth period were 47.3%,149.8% and 309.7%,respectively,of the control,whereas the yield decreased to 68.6% of the control. In addition,our results demonstrated that the leachate at lower levels could promote growth. This is mainly embodied in that the yield of maize treated with 10%leachate at the soaking stage increased to 116.0% of the control. Moreover,the cytological analysis experiment also demonstrated that the ecological risk of leachate still exists in both cases. furthermore,the gray relational analysis showed that the ear row number and tassel branch number were the major factors affecting the yield of maize treated with 50%leachate at the stages of soaking and germination,respectively. In general,these results are helpful in understanding the phytotoxicity of leachate,which provides additional reference data for risk assessment and management of leachate.

关键词： Landfill leachate Maize Phytotoxicity Seed soaking Germination

Thermal and Redox Dual Responsive Poly(L-glutamate)with Oligo(ethylene glycol)Side-chains

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Chinese Journal of Polymer Science 2016年第12期34卷 1436-1447页

作者： Xiao-hui fu Yi-nan Ma 孙静李志波 School of Polymer Science and Engineering Qingdao University of Science and Technology Laboratory of Polymer Physics and Chemistry Institute of Chemistry Chinese Academy of Sciences

A series of poly（L-glutamate）s grafted with oligo（ethylene glycol）（OEG） side-chains through the thioether linkages （PALGn-g-EGx, x = 2, 3 and 4） were prepared by ring-opening polymerization （ROP） of γ-allyl-L-glutamate N-carboxyanhydride （ALG-NCA） and thiol-ene photoaddition. The chemical structures and physical properties were characterized by 1H-NMR, Fourier transform infrared （FTIR）, circular dichroism （CD）, etc. The PALGn-g-EGx samples with x = 3 and 4 displayed lower critical solution temperature （LCST） in water due to the presence of OEG units. The clouding point （CP） of polypeptides can be finely tuned by changing the side chain structures, molecular weights and sample concentrations. In addition, the thioether linkages in the side chains offer additional redox-responsive properties. The influence of both OEG units and thioether linkages on the LCST behavior was systematically investigated. This work provides an efficient way to prepare multi-stimuli responsive materials with highly tunable properties.

关键词： N-carboxyanhydride (NCA) Polypeptide Ring-opening polymerization Click chemistry Stimuli-responsive.

A Multi-interlayer LMAS Joint of C/C-SiC Composites and LAS Glass Ceramics

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Journal of Materials Science & Technology 2015年第5期31卷 467-472页

作者： Qiangang fu Fengling Zhao Hejun Li Han Peng Xiaoying nan C/C Composites Research Center State Key Laboratory of Solidification ProcessingNorthwestern Polytechnical University

Porous C/C-SiC composites were prepared through a two-step chemical vapor infiltration process,and a multi-interlayer joint of Li20-MgO-Al2O3-SiO2（LMAS） was applied to join C/C-SiC composites and lithium aluminum silicate（LAS） glass ceramics by means of a vacuum hot-pressing *** of SiC whiskers were generated in the pores of low-density C/C composites during chemical vapor deposition process,which is essentia! to form a zigzag interface structure between C/C-SiC substrate and the LMAS *** average shear strength of the LMAS joint was improved from 12.17 to 19.91 MPa after changing the composites from high-density C/C composites（1.75 g/cm3） with a CVD-SiC coating to the C/C-SiC composites with a low density（1.48 g/cm3）.The improvement of the joint strength is mainly attributed to the formation of the inlay structure at the SiC-C/C and SiC-LMAS interfaces.

关键词： C/C-SiC Interface Interlayer Joining and ceramic

Smart homing guidance strategy with control saturation against a cooperative target-defender team

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Journal of Systems Engineering and Electronics 2019年第2期30卷 366-383页

作者： GUO Hang fu Wenxing fu Bin CHEN Kang yan Jie School of Astronautics Northwestern Polytechnical University

A smart homing guidance strategy with control saturation against a target-defender team is derived. It is noteworthy that a cooperative strategy of the target-defender team is applied,which has been proved more challenging for the homing *** defender missile is launched by the target and guided by a cooperative augmented proportional navigation(APN). At the same time, the target performs a one-switch maneuver to cooperate and minimize the defender's acceleration requirement. The problem is analyzed for arbitrary-order linear dynamics of the agents in the linearized form but validated by the mathematical simulations by using nonlinear kinematics. The perfect information of three agents' states is assumed. Then, a method to deal with the target-defender team is proposed. It contains a combined performance index penalizing the miss distance relative to the target and energy consumption in the whole duration. Besides, the specific miss distance related to the defender is regarded as an inequality constraint. An analytical solution for the smart guidance strategy against the APN guided defender is derived. Meanwhile, the control saturations are introduced to get more realistic and reasonable insights to this practical target-missile-defender problem. A simple but effective iterative searching technique is proposed to determine the saturation time points. The solution provides an optimal homing strategy to evade the defender with a specific miss distance and intercept the target with the minimum miss distance in the minimum energy manner. Nonlinear two-dimensional simulation results are used to validate the theoretical analysis. By comparison with the optimal differential game guidance(ODGG) and the combined minimum effort guidance(CMEG), the superiority of this smart guidance strategy is concluded.

关键词： smart homing guidance control saturation targetmissile-defender iterative searching technique

Current prophylactic strategies against hepatitis B virus recurrence after liver transplantation

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World Journal of Gastroenterology 2009年第20期15卷 2489-2499页

作者： Li Jiang Li-Sheng Jiang nan-Sheng Cheng Lu-nan yan Department of Liver and Vascular Surgery Liver Transplantation Center West China Hospital of Sichuan University Chengdu 610041 Sichuan Province China Department ofBiliary Surgery West China Hospital of Sichuan University Chengdu 610041 Sichuan Province China

Prophylactic strategies against hepatitis B virus(HBV) recurrence after liver transplantation(LT) are essential for patients with HBV-related *** LT, lamivudine(LAM) was proposed to be down-graded from first-to second-line *** contrast, adefovir dipivoxil(ADV) has been approved not only as first-line therapy but also as rescue therapy for patients with LAM ***, combination of ADV and LAM may result in lower risk of ADV resistance than ADV *** new drugs such as entecavir, telbivudine and tenofovir, are probably candidates for the treatment of hepatitis-B-surface-antigen-positive patients awaiting *** LT, low-dose intramuscular hepatitis B immunoglobulin(HBIG), in combination with LAM, has been regarded as the most cost-effective regimen for the prevention of post-transplant HBV recurrence in recipients without pretransplant LAM resistance and rapidly accepted in many transplant *** the introduction of new antiviral drugs, new hepatitis B vaccine and its new adjuvants, post-transplant HBIG-free therapeutic regimens with new oral antiviral drug combinations or active HBV vaccination combined with adjuvants will be promising, particularly in those patients with low risk of HBV recurrence.

关键词： Hepatitis B virus Liver transplantation Recurrence Prophylaxis Hepatitis B immunoglobulin

Lean-non-alcoholic fatty liver disease increases risk for metabolic disorders in a normal weight Chinese population

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World Journal of Gastroenterology 2014年第47期20卷 17932-17940页

作者： Ren-nan Feng Shan-Shan Du Cheng Wang yan-Chuan Li Li-yan Liu fu-Chuan Guo Chang-Hao Sun Department of Nutrition and Food Hygiene School of Public HealthHarbin Medical University Department of Environmental Hygiene School of Public HealthHarbin Medical University

AIM: To study the prevalence and clinical biochemical, blood cell and metabolic features of lean-non-alcoholic fatty liver disease (lean-NAFLD) and its association with other diseases.

关键词： Lean-non-alcoholic fatty liver disease Metabolic disorder Diabetes Risk Chinese

Effect of Hydrophobic Modification on the Durability and Environmental Properties of Porous MgF_2 Antireflective Films

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Acta Metallurgica Sinica(English Letters) 2014年第4期27卷 649-655页

作者： Lianghong yan nan Liu Songnan Zhao Hongwei yan Haibing L Xiaodong Yuan Research Center of Laser fusion China Academy of Engineering Physical

Conventional porous MgF2 antireflective films show poor environmental durability due to its hydrophilic *** improve the film environmental durability,hydrophobic porous MgF2 antireflective films are prepared by a methyl silicone-modified MgF2 *** of the methyl silicone proportions on the film properties are examined in order to control the wettability,peak transmittance,and environmental durability of the *** modification of methyl silicone can increase the film hydrophobicity,thus decreases the adsorption of water,and improves the environmental ***,large amounts of methyl silicone could increase the film refractive index,resulting in the decrease in peak transmittance for films on BK7 *** with 40% silicone show water contact angle of 110°,peak transmittance of 98.7%,and good environmental *** results of accelerated test show that the environmental durability of the porous MgF2 films modified with 40% methyl silicone is six times higher than that of the conventional films.

关键词： Porous MgF2 Antireflective film Environmental durability Hydrophobicity

A combined quality evaluation method that integrates chemical constituents, appearance traits and origins of raw Rehmanniae Radix pieces

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Chinese Journal of Natural Medicines 2021年第7期19卷 551-560页

作者： GU Min YUAN Yi-Ping QIN Zi-nan XU yan SHI nan-nan WANG yan-Ping ZHAI Hua-Qiang QIAN Zhong-Zhi Standardization Research Center of Traditional Chinese Medicine Dispensing Beijing University of Chinese MedicineBeijing 102488China Institute of Basic Research in Clinical Medicine China Academy of Chinese Medical SciencesBeijing 100700China National Pharmacopoeia Commission Beijing 100061China

The quality control of Chinese herbal medicine is a current challenge for the internationalization of traditional Chinese *** quality evaluation methods lack quantitative analysis,while modern quality evaluation methods ignore the origins and appearance ***,an integrated quality evaluation method is urgent in *** Rehmanniae Radix(RRR)is commonly used in Chinese herbal *** present,much attention has been drwan towards its quality control,which however is limited by the existing quality evaluation *** present study was designed to establish a comprehensive and practical method for the quality evaluation and control of RRR pieces based on its chemical constituents,appearance traits and ***-three batches of RRR pieces were collected from six provinces,while high-performance liquid chromatography(HPLC)was applied to determine the following five constituents,including catalpol,rehmannioside A,rehmannioside D,leonuride and verbascoside in RRR *** appearance traits were quantitatively ***,correlation analysis,principal components analysis(PCA),cluster analysis and t-test were performed to evaluate the qualities of RRR *** batches of RRR pieces were divided into three categories:samples from Henan province,samples from Shandong and Shanxi provinces,and those from other ***,the chemical constituents and appearance traits of RRR pieces were significantly different from diverse *** combined method of chemical contituents,appearance traits and origins can distinguish RRR pieces with different qualities,which provides basic reference for the quality control of Chinese herbal medicine.

关键词： Bioactive constituents Raw Rehmanniae Radix Quality evaluation Appearance traits Different origins

Engineering N3C vacancies in hierarchical porous carbon nitride nanosheets for room temperature ultradeep photocatalytic aerobic oxidative desulfurization

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Science China Chemistry 2025年

作者： Yina Nie Weijie yang Xin Wang Xiang Li Lele Wei Xiaolin Bai Lin Liu Feng fu Jun Wan College of Chemistry & Chemical Engineering Research Institute of Comprehensive Energy Industrial Technology Shaanxi Key Laboratory of Chemical Reaction Engineering Yan'an University Anhui Engineering Research Center of Carbon Neutrality College of Chemistry and Materials Science Anhui Normal University

The production of ultra-low sulfur clean fuels holds global significance for improving energy efficiency and reducing environmental pollution. Photocatalytic aerobic oxidative desulfurization（PODS） offers an attractive approach to efficiently remove refractory heterocyclic aromatic sulfur compounds under mild conditions. However, the sluggish charge dynamics,insufficient molecule activation, and slow mass transfer within photocatalysts restrict the overall desulfurization efficiency,hindering the widespread application of this technology. Herein, we developed a defective g-C3N4（M1U3CN） photocatalyst with bridged N3Cvacancies and hierarchical porous structures to address these limitations. This catalyst not only demonstrates outstanding dibenzothiophene（DBT） removal efficiency of 99.6% for model oil with high conversion and selectivity but also achieves complete sulfur removal from gasoline as well as 96.7% sulfur removal for distilled diesel at room temperature,successfully achieving ultradeep aerobic oxidative desulfurization. The introduction of rich N3Cvacancies and abundant micromeso-macroporous distribution in M1U3CN enhances kinetic efficiencies by promoting charge carrier separation, mass transfer,and molecular activation simultaneously; resulting in exceptional PODS performance. This work provides a collaborative strategy to overcome kinetic challenges in aerobic oxidative desulfurization via defect and structural engineering of the catalyst.

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Deformation Mechanism and Hot Workability of Extruded Magnesium Alloy AZ31

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Acta Metallurgica Sinica(English Letters) 2018年第1期31卷 71-81页

作者： Zhao-yang Jin nan-nan Li Kai yan Jian Wang Jing Bai Hongbiao Dong School of Mechanical Engineering Yangzhou University School of Physics and Optoelectronic Engineering Nanjing University of Information Science and Technology School of Materials Science and Engineering Southeast University Department of Engineering University of Leicester

Using the flow stress curves obtained by Gleeble thermo-mechanical testing, the processing map of extruded magnesium alloy AZ31 was established to analyze the hot workability. Stress exponent and activation energy were calculated to characterize the deformation mechanism. Then, the effects of hot deformation parameters on deformation mechanism, microstructure evolution and hot workability of AZ31 alloy were discussed. With increasing deformation temperature, the operation of non-basal slip systems and full development of dynamic recrystallization （DRX） contribute to effective improvement in hot workability of AZ31 alloy. The influences of strain rate and strain are complex. When temperature exceeds 350 ℃, the deformation mechanism is slightly dependent of the strain rate or strain. The dominant mechanism is dislocation cross-slip, which favors DRX nucleation and grain growth and thus leads to good plasticity. At low temperature （below 350 ℃）, the deformation mechanism is sensitive to strain and strain rate. Both the dominant deformation mechanism and inadequate development of DRX deteriorate the ductility of AZ31 alloy. The flow instability mainly occurs in the vicinity of 250 ℃ and 1 s^-1.

关键词： Hot workability. Deformation mechanism Dynamic recrystallization Activation energy Magnesium alloy