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Ultraviolet irradiation induced oxidative stress and response of antioxidant system in an intertidal macroalgae Corallina officinalis L.

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Journal of Environmental Sciences 2010年第5期22卷 716-722页

作者： lixia li Jiqiang Zhao Xuexi Tang College of Marine life Science Ocean University of China Qingdao 266003 China Chemistry and Biology College Yan Tai University Yantai 264005 China

The response of the antioxidant defense system of an intertidal macroalgae Corallina officinalis *** different dosages of UV-B irradiation was *** showed that superoxide dimutase （SOD） and peroxidase （POX） increased and then maintained at a relatively stable level when subjected to UV-B *** （CAT） activity under medium dosage of UV-B irradiation （Muv） and high dosage of UV-B irradiation （Huv） treatments were significantly *** peroxidase （APX） activity first remained unaltered and then increased in Huv *** addition,the assay on isozymes was carried out using non-denaturing polyacrylamide gel electrophoresis （PAGE）.The activities of some SOD isoforms were altered by *** new bands （POX V and POX VII） appeared upon exposure to all three UV-B *** III activity was increased by low dosage of UV-B irradiation （Luv）,whereas CAT III and CAT IV disappeared when the alga was exposed to Muv and *** bands of APX （APX VI and APX VII） were increased and a new band （APX X） was observed under Huv exposure.H 2 O 2 and thiobarbituric acid reacting substance （TBARS） increased under Muv and Huv ***,UV-B protection mechanisms are partly inducible and to a certain extent sufficient to prevent the accumulation of damage in ***.

关键词： UV-B irradiation Corallina officinalis L. superoxide dimutase catalase ascorbate peroxidase peroxidase

An Analysis of Salt Policy Reform and Central Fiscal Crisis in Late Qing Dynasty

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学术界 2015年第6期 257-266页

作者： li lixia School of History and Culture Henan Normal University

In late Qing Dynasty,the Central Government was faced with the problem of financial dysfunction and financial power decentralization. In order to cope with the fiscal crisis and solve the economic difficulties as well as regain control of financial rights,the government carried out the salt policy reform,which directly injured the interests of local governors,causing them to unite against the central financial authority. Although the attempt to regain control of financial power had not been successful,there was an expansion of central government functions in financial field.

关键词： salt policy reform at the end of Qing Dynasy fiscal crisis function expansion of the central government

A Modified Elastoplastic Contact Stiffness Model Considering Continuous Smooth Contact Characteristics and Substrate Deformation

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Acta Mechanica Solida Sinica 2021年第5期34卷 754-765页

作者： ling li Jingjing Wang Xiaohui Shi Meijuan Tong lixia li School of Mechanical and Electrical Engineering Xi’an University of Architecture and TechnologyXi’an710055China

The contact stiffness of the joint surface directly affects the static and dynamic mechanical behavior,and accuracy of the machine tool.A new elastoplastic contact stiffness model is proposed by considering continuous and smooth contact characteristics and substrate ***,the interpolation interval of cubic Hermite polynomials is improved to meet the continuous and smooth change of contact parameters during asperity ***,the micro-contact mechanism considering substrate deformation is explored by establishing an asperity-substrate system ***,combined with statistical principles,a new contact stiffness model of the joint surface is ***,the correctness of the built model is verified by comparing with experimental data and different contact *** simulation results show that the model changes continuously and smoothly in the three deformation *** substrate deformation mainly affects the asperities in the elastic contact *** smoother is the surface,the more significant is the influence of substrate deformation.

关键词： Joint surface Contact stiffness Continuous smooth contact characteristics Substrate deformation

Cultivation of Teaching Skills： Problems and Solutions

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学术界 2016年第3期 309-313页

作者： li lixia School of History and Culture Henan Normal University Xinxiang Henan 453007

The training of normal students' skills in higher normal universities is the premise and basis for their future employment. At present,there are a lot of problems in normal universities in the training of teachers' skills,such as unscientific arrangement of curriculum in normal universities,lack of vocational skills training,discrepancy between knowledge and skills,shortage of the training,the poverty of the methods and imperfection of evaluation system and so on. In order to improve the modern information teaching skills of the students of normal universities,broaden the paths of employment and improve the level of running a school,we should adjust the curriculum set,strengthen the teachers' quality,deal with the relationship between theory and practice appropriately,pay attention to integration of academic skills training,and build a scientific evaluation system.

关键词：教学技能职业技能培训培养课程设置高师院校评价体系技能训练师范院校

Effects of brain-derived neurotrophic factor on induced differentiation of SH-SY5Y cells in vitro

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Neural Regeneration Research 2009年第12期4卷 1062-1067页

作者： Jiao li Jingqi li Xueli li lixia Lu Lei Xu Department of Biochemistry and Molecular Biology Medical School Tongji University Shanghai 200092 China

BACKGROUND： Previous studies have demonstrated that brain-derived neurotrophic factor （BDNF） promotes neural differentiation. However, the mechanisms involved in cell cycle-related protein regulation, which highly correlates to neural proliferation and apoptosis, remain poorly understood. OBJECTIVE： To investigate the effects of various concentrations of BDNF on cycle-related protein mRNA expression in induce-differentiated SH-SY5Y cells in vitro prior to and following G2 phase, and to analyze the neuroprotective effects of BDNF. DESIGN, TIME AND SETTING： A comparison, observational study, based on cell biology, was performed at the Department of Biochemistry, Medical College of Tongji University, from March 2005 to October 2006. MATERIALS： SH-SY5Y cells were provided by Shanghai Institute of Cytology, Chinese Academy of Science; BDNF by Alomone Labs, Israel; all-trans retinoic acid （ATRA） by Sigma-Aldrich, USA. METHODS： SH-SY5Y cells were randomly divided into three groups： blank control [cells were treated in Insulin-Transferrin-Selenium （ITS） solution for 7 days], ATRA （cells were treated with ITS solution containing 10 μmol/L ATRA for 7 days）, and BDNF （cells were treated identical to the ATRA group for 5 days, and then respectively treated in ITS solution containing 1, 10, and 100 μg/L BDNF for 2 days）. The experiment was repeated three times for each group. MAIN OUTCOME MEASURES： mRNA expression levels of cyclin A1, B1, B2, cyclin-dependent kinase 1, and 5 were detected using quantitative real-time RT-PCR; percentage of cells in G1, S, and G2 phases were detected using fluorescence-activated cell sorting. RESULTS： mRNA expression levels of cyclin A1 in the high-dose BDNF group was significantly less than the ATRA group （P 〈 0.05）.mRNA expression levels of cyclin B1 was significantly less in the different BDNF concentration groups compared with the control and ATRA groups （P 〈 0.05 or P 〈 0.01）. mRNA expression levels of cyclin B2 and cyclin-dependent kinase 1

关键词： brain-derived neurotrophic factor induced differentiation cell cycle-related protein quantitative real-time RT-PCR fluorescence-activated cell sorting SH-SY5Y cell line

Innovative pre-concentration technology for recovering ultrafine ilmenite using superconducting high gradient magnetic separator

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International Journal of Mining Science and Technology 2021年第6期31卷 1043-1052页

作者： Zhitao Yuan Xuan Zhao Jiwei Lu Hong Lv lixia li School of Resources and Civil Engineering Northeastern UniversityShenyang 110819China BGRIMM Technology Group Beijing 100160China China ENFI Engineering Co. Ltd.Beijing 100038China

To achieve the utilization of the abandoned ultrafine ilmenite(-20 μm) produced in the titanium magnetite processing plant in Panzhihua,the superconducting high-gradient magnetic separation(SMS) technology was proposed in this *** optimizing the conditions of magnetic intensity,feeding and pulsation,an SMS concentrate with TiO_(2) grade of 16.03% and TiO_(2) recovery of 66.39% was obtained through one roughing-one cleaning pre-concentration *** specific magnetic force and magnetic force were calculated and analysed to illustrate the pre-concentration mechanism,and the results revealed that the combination of high magnetic field and strong pulsating resulted in the effective preconcentration of the ultrafine ilmenite in the SMS *** addition,the magnetic force analysis indicated that the high magnetic intensity and high magnetic gradient are the key factors of the SMS ***,the EDS-Mapping detection certified that the ultrafine ilmenite was concentrated from the gangue minerals using SMS technology.

关键词： Ultrafine ilmenite Superconducting high gradient magnetic separation Pre-concentration EDS-Mapping

Preparation of porous semi-IPN temperature-sensitive hydrogel-supported nZVI and its application in the reduction of nitrophenol

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Journal of Environmental Sciences 2019年第8期31卷 93-102页

作者： lixia li Ruiwei Wang Xiaodong Xing Wenqiang Qu Shutong Chen Yunlong Zhang School of Environment and safety engineering Jiangsu University School of Chemical Engineering Nanjing University of Science and Technology

Nanoscale zero-valent iron(n ZVI) particles supported on a porous, semi-interpenetrating(semi-IPN), temperature-sensitive composite hydrogel(PNIPAm-PHEMA). n ZVI@PNIPAmPHEMA, was successfully synthesized and characterized by FT-IR, SEM, EDS, XRD and the weighing method. The loading of nZVI was 0.1548 ± 0.0015 g/g and the particle size was30–100 nm. NZVI was uniformly dispersed on the pore walls inside the *** of the well-dispersed n ZVI, the highly porous structure, and the synergistic effect of PNIPAm-PHEMA, nZVI@PNIPAm-PHEMA showed excellent reductive activity and wide p H applicability. 95% of 4-NP in 100 m L of 400 mg/L 4-NP solution with initial p H 3.0–9.0 could be completely reduced into 4-AP by about 0.0548 g of fresh supported n ZVI at 18–25 °C under stirring(110 r/min) within 45 min reaction time. A greater than 99% 4-NP degradation ratio was obtained when the initial p H was 5.0–9.0. The reduction of 4-NP by nZVI@PNIPAm-PHEMA was in agreement with the pseudo-first-order kinetics model with Kobsvalues of 0.0885–0.101 ***@PNIPAm-PHEMA was able to be recycled, and about 85% degradation ratio of 4-NP was obtained after its sixth reuse cycle. According to the temperature sensitivity of PNIPAmPHEMA, n ZVI@PNIPAm-PHEMA exhibited very good storage stability, and about 88.9%degradation ratio of 4-NP was obtained after its storage for 30 days. The hybrid reducer was highly efficient for the reduction of 2-NP, 3-NP, 2-chloro-4-nitrophenol and 2-chloro-4-nitrophenol. Our results suggest that PNIPAm-PHEMA could be a good potential carrier, with n ZVI@PNIPAm-PHEMA having potential value in the application of reductive degradation of nitrophenol pollutants.

关键词： Porous semi-IPN temperature sensitive hydrogel Supported nanoscale zero-valent iron Reductive degradation Nitrophenol Storage stability

Optimization of hot-air microwave combined drying control system based on air outlet temperature and humidity monitoring

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International Journal of Agricultural and Biological Engineering 2021年第4期14卷 255-261页

作者： Fujie Zhang Anqi’er Hu Ruikai Song lixia li Faculty of Agriculture and Food Kunming University of Science and TechnologyKunming 650500China Mechanization Engineering Research Center of Yunnan Province Colleges and Universities Kunming 650500China

Microwave drying is one of the most important drying methods in *** online measurement and control of material dried,as a challenging research issue,is helping to improve the drying quality of the final product and the energy utilization efficiency of microwave *** order to realize the online measurement of temperature in microwave drying,a detection strategy was based on the temperature and humidity monitoring at the air outlet of coupling hot air and microwave drying *** programming software was employed to collect the temperature and humidity signal value at the outlet of the dryer to estimate the drying degree of the *** to the amount of moisture removal in real-time,the microwave input power was adjusted gradually in the microwave drying *** potato as material dried,the microwave power of microwave and hot air coupling drying is monitored to realize the real-time *** results showed that the total color difference value of the product of 3.09,the rehydration ratio of 2.92,the unit energy consumption of 17419.35 kJ/kg,and the drying rate of 0.442 g/s were *** minimum comprehensive weighted score of the product was *** with the orthogonal experiment,the optimal drying process was obtained as the total color difference value of the product of 2.84,the rehydration ratio of 3.01,the unit energy consumption of 17419.35 kJ/kg,and the drying rate of 0.397 g/*** minimum comprehensive weighted score of the product was 20.67,and the difference was not *** control strategy not only solves the non-uniform phenomenon of drying,and makes the microwave drying real-time and continuous,but also improves the drying efficiency and quality.

关键词： microwave drying temperature humidity control power potato

UV-B irradiation and allelopathy by Sargassum thunbergii affects the activities of antioxidant enzymes and their isoenzymes in Corallina pilulifera

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Journal of Oceanology and limnology 2022年第5期40卷 1950-1962页

作者： Ming liU Jiqiang ZHAO Yujuan PANG lipei ZHANG Fuhua BIAN lixia li College of life Sciences Yantai UniversityYantai 264005China Yantai Jien Biotechnology Co. Ltd.Yantai 264006China

Intertidal macroalgae can cope with the dual effects of UV-B irradiation and *** study the impacts of the two stressors,we co-cultured Corallina pilulifera with Sargassum thunbergii in 1:1 and 1:10 ratios under different doses of UV-B *** response of the antioxidant defense system,focusing on activities of superoxide dismutase(SOD),ascorbate peroxidase(APX),peroxidase(POX)and glutathione reductase(GR),was *** addition,isoenzyme patterns were analyzed using nondenaturing poly acry lamide gel *** results show that the activities of SOD,APX,and GR were all significantly affected by both UV-B radiation and allelopathy,and the effect of their interaction was ***,POX activity was only influenced by UV-B *** enzymatic assay revealed four distinct bands of *** SODⅢband weakened significantly when the co-cultures were exposed to extremely high dosage of UV-B irradiation under both co-culturing ratios of 1:1 and 1:*** the coculturing ratio was 1:10,both POXⅡand APXⅡenzy me activities increased with different UV-B *** activity was at its greatest when the co-culture ratio was 1:10 and exposure was to the higher UV-B *** activities of GRⅢand GRⅣwere elevated under all UV treatments whereas the activities of GRI and GRII were reduced under the lower UV-B treatments but were elevated under the higher UV-B ***,lipid peroxidation,as indicated by the thiobarbituric acid-reacting substance(TBARS)assay,increased significantly under the dual *** data sugge st that allelopathy and UV-B radiation stre ss can each affect the antioxidant enzyme activities of ***,the adverse effects of UV-B on *** were intensified by the compounding effects of allelopathy.

关键词： Corallina pilulifera antioxidant system isoenzymes UV-B radiation allelopathy