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Unconditional basis recursively generated in L^p on compact sets

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Science China Mathematics 2005年第12期48卷 1707-1720页

作者： li Bingzheng li jun Department of Mathematics Zhejiang UniversityHangzhou 310028China Department of MathematicsZhejiang UniversityHangzhou 310028China

We construct an unconditional basis in the Banach space Lp(Ω, ρ) for p ＞ 1 by using the refinement equation and the basic operation of translation and scale, where Ω is a compact subset in Rn. We also give an algorithm of how to construct an unconditional basis in Lp(Ω, ρ). At the end of this paper, we give the characterization of the functions in Lp(Ω, ρ) by using the wavelet coefficients.

关键词： unconditional basis,wavelets,multiresolution analysis,simple martingale.

Flow Injection Determination of Oxalate Based on Its Catalytic Effect on the Oxidation of p-Chloride Aniline by Dichromate

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Chemical Research in Chinese Universities 2001年第3期17卷 253-258页

作者： li li-jun WEI Hong-guang ZHANG Ying Guangxi Institute of Technology Liuzhou 545006P.R.China

In a sulfuric acid medium, oxalate exhibits a strong catalytic effect on the oxidation of p-chloride aniline(ClBN) by dichromate, and the red oxidation product of ClBN has a maximum absorhancy at 520 nm. Based on this founding, a new FI method for determining oxalate was developed. A calibration curve of oxalate in the range of 0.40—17.0μg/mL was obtained. The detection limit was 0.10μg/mL. Sampling rate was 103-samples/h. The possible interference by the co-existing substances or ions was examined. This new method was applied to the determination of micro amounts of oxalate in real samples with satisfactory results.

关键词： FIA Oxalate p-Chloro aniline Potassium dichromate

Multivariate Rational Response Surface Approximation of Nodal Displacements of Truss Structures

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Chinese Journal of Mechanical Engineering 2018年第1期31卷 100-113页

作者： Shan Chai Xiang-Fei Ji li-jun li Ming Guo School of Transportation and Vehicle Engineering Shandong University of Technology Key Laboratory of Electronic Equipment Structure Design Xidian University Shandong linglong Tire Co. Ltd.

Polynomial-basis response surface method has some shortcomings for truss structures in structural optimization,concluding the low fitting accuracy and the great computational effort. Based on the theory of approximation, a response surface method based on Multivariate Rational Function basis(MRRSM) is proposed. In order to further reduce the computational workload of MRRSM, focusing on the law between the cross-sectional area and the nodal displacements of truss structure, a conjecture that the determinant of the stiffness matrix and the corresponding elements of adjoint matrix involved in displacement determination are polynomials with the same order as their respective matrices, each term of which is the product of cross-sectional areas, is proposed. The conjecture is proved theoretically for statically determinate truss structure, and is shown corrected by a large number of statically indeterminate truss structures. The theoretical analysis and a large number of numerical examples show that MRRSM has a high fitting accuracy and less computational effort. Efficiency of the structural optimization of truss structures would be enhanced.

关键词： Multivariate rational function Response surfaces method Truss structures Structure optimization

Derivation and validation of soil total and extractable cadmium criteria for safe vegetable production

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Journal of Integrative Agriculture 2023年第12期22卷 3792-3803页

作者： li li-jun li Kun JIANG Bao li Ju-mei MA Yi-bing Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural SciencesBeijing 100081P.R.China Sichuan Academy of Forestry Sichuan 610081P.R.China National Urban Environmental Pollution Control Engineering Research Center Beijing Municipal Research Institute of Environmental ProtectionBeijing 100037P.R.China National Observation and Research Station of Coastal Ecological Environments in Macao/Macao Environmental Research Institute Macao University of Science and TechnologyMacao SAR 999078P.R.China

Determining the appropriate soil cadmium(Cd)criteria for vegetable production is important for ensuring that the Cd concentrations of the vegetables meet food safety *** soil extractable Cd criteria for vegetable production are also essential for both food safety and environmental management,especially in areas with a high natural background *** the present study,soil total and extractable Cd criteria were derived using the approach of species sensitivity distribution integrated with soil aging and bioavailability as affected by soil properties.A dataset of 90 vegetable species planted in different soils was compiled by screening the published in literature in five bibliographic databases using designated search *** empirical soil-plant transfer model was applied to normalize the bioaccumulation *** normalization,the intra-species variability was reduced by 18.3 to 84.4%.The soil Cd concentration that would protect 95%(HC_(5))of the species was estimated by species sensitivity distribution curves that were fitted by the Burr III *** soil Cd criteria derived from the added approach for risk assessment were proposed as continuous criteria based on a combination of organic carbon and pH in the *** for total Cd and EDTA-extractable Cd in the soil ranged from 0.23 to 0.61 mg kg^(-1)and from 0.09 to 0.25 mg kg^(-1),*** experimental data were used to validate the applicability and validity of these *** of the predicted HC5 values in the field experimental sites were below the 1:1 *** results provide a scientific basis for soil Cd criteria for vegetable production that will ensure food safety.

关键词： Cd vegetables soil criteria species sensitivity distribution soil extractable Cd criteria

Determination of Vitamin B_1 in Pharmaceutical Preparations by Flow-injection Analysis with Biamperometric Detection

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Chemical Research in Chinese Universities 2005年第6期21卷 650-653页

作者： li li-jun CHENG Hao ZHAO Chuan HU Xiao-ge Department of Biological and Chemical Engineering Guangxi University of Technology Liuzhou 545006 P. R. China Institute of Analytical Science Northwest University Xi＇an 710069 P. R. China

A new electrochemical method for the on-line determination of vitamin B1 is presented. Based on dead-stop endpoint biamperometry by using two platinum foil electrodes with an applied potential difference of 150 mV, vitamin B1 can be oxidized by hexacyanoferrate （ Ⅲ ） in a sodium hydroxide medium via a reversible indicating couple Fe（ CN）6^4- /Fe（CN）6^3- The cell current is linear with the concentration of vitamin B1 in the concentration range of 4. 0 × 10^-6-1.0 × 10^ -3 mol/L with a detection limit of 8.0 ×10 ^-7 mol/L（0. 27 μg/mL）. Most familiar excipients, ions and vitamins do not interfere with the determination of vitamin B1. The method displays the advantages of simplicity, high efficiency（ 180 samples/h）, and high selectivity, and is suitable for the determination of vitamin B1 in pharmaceutical preparations.

关键词： Pharmaceutical analysis Biamperometry Vitamin B1 How-injection analysis

Effects of TRPC6 on invasibility of low-differentiated prostate cancer cells

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Asian Pacific Journal of Tropical Medicine 2014年第1期7卷 44-47页

作者： Dong Wang Xiang li Jing liu jun li li-jun li Ming-Xing Qiu Department of Urology Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital Department of Urology West China Hospital of Sichuan University

Objective:To study the expression of TRPC6 among prostate cancer cells,establish high expression cell lines of TRPC6,and to provide potential cell mode for prostate cancer oncogenesis and ***:Occurrence and development of prostate cancer cells,PC3,PC—3m DU145,22 rvl,LNCaP and normal prostate epithelial cells in the PrEC TRPC6 expression level were detected by QPCR *** phosphate transfection method was used to package retrovirus pLEGFP-Nl-TRPC6 and pLEGFP-Nl-vector and infect the prostate cancer cells,a stable high expression of TRPC6 prostate cancer *** cell lines of TRPC6,matrix metalloproteinase(MMP)2,MMP9 expression was detected by QPCR and Western *** of cell invasion ability was detected by ***:The expression level of prostate cancer cells TRPC6 were higher than control group PrEC *** TPRC6 the expression of cell line PC 3 transfer potential wre the lowest,and high transfer cell tone PC-3M express was the ***-time fluorescent quantitative PCR and western blot results showed that after filter,the seventh generation of cell TRPC6 protein and mRNA expression levels were higher than the control group *** experimental results showed that the overexpression of TRPC6could promote the invasion ability of PC.3 prostate cancer ***:TRPC6 expressed in prostate cancer cells is in disorder,and its action may be associated with the invasion and metastasis of prostate cancer cells;successful establishment of stable high expression of TRPC6prostate cancer cells primarily confirm the invasion-trigger ability of TRPC6 on prostate cancer,and lay down the foundation for exploring the TRPC6's role in the occurrence and development of prostate cancer

关键词： TRPC6 Prostate cancer Retroviruses Stable cell line invasion

Determination of ephedrine and codeine in human urine by cation-selective exhaustive injection and sweeping micellar electrokinetic chromatography

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Chinese Chemical Letters 2009年第1期20卷 84-87页

作者： li jun li Si Guang li Hai Yan li Zhuo Cai Hao Cheng Department of Biological and Chemical Engineering Guangxi University of Technology Liuzhou 545006 China College of Chemistry and Chemical Engineering Guangxi University Nanning 530004 China Zhongshan School of Medicine Sun-Yat-Sen University Guangzhou 510080 China

A sensitive method for the determination of ephedrine and codeine in human urine by capillary electrophoresis （CE） was described. In order to improve the sensitivity, two online concentration techniques including cation-selective exhaustive injection （CSEI） and sweeping micellar electrokinetic chromatography （sweeping-MEKC） were used. Under the optimum conditions, the detection limits （S/N = 3） were 0.10 μg/L for ephedrine and 0.80 μg/L for codeine. This method was successfully applied to real urine sample analysis.

关键词： Cation-selective exhaustive injection Sweeping miceUar electrokinetic chromatography Ephedrine Codeine

Dipping Paint Curing Amorphous U-Core Used as Reactor

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Journal of Iron and Steel Research International 2013年第7期20卷 63-68页

作者： li Guang-min li De-ren liU Tian-cheng li li-jun LU Zhi-chao China Iron and Steel Research Institute Group Advanced Technology and Materials Co. Ltd.

Non-oriented silicon steel （35W310） and amorphous ribbon （FeT8 Si9B13 amorphous alloy） reactor U-cores are made by welding and dipping paint curing, respectively. Amorphous U-core used to make reactor cut sharply ed-dy current loss due to high electrical resistivity characteristic, thickness of thin ribbon and insulation of dipping paint. The amorphous alloy has high and constant magnetic permeability, and is more suitable for reactor design power to filter high order harmonic component. Keeping off high magnetostriction district with magnetic flux density of 50-100 mT can weaken influence on inductance of inductor due to elongation of magnetostriction. Amorphous al-loy has a lower temperature rise using the software Infolytica 7.2 simulation.

关键词： amorphous Fe-Si-B alloy dipping paint curing power loss reactor U-core magnetic field simulation

Design considerations for electromagnetic couplers in contactless power transmission systems for deep-sea applications

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Journal of Zhejiang University-Science C(Computers and Electronics) 2010年第10期11卷 824-834页

作者： Ze-song li De-jun li lin liN Ying CHEN State Key Lab of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027. China

In underwater applications of contactless power transmission(CLPT) systems,high pressure and noncoaxial operations will change the parameters of electromagnetic(EM) *** a result,the system will divert from its optimum *** a reluctance modeling method,we investigated the gap effects on the EM coupler in deep-sea *** and measurements were performed to analyze the influence of high pressure and noncoaxial alignments on the *** was shown that it is useful to set a relatively large gap between cores to reduce the influence of *** were carried out to verify the transferring capacity of the designed coupler and system for a fixed *** results showed that an EM coupler with a large gap can serve a stable and efficient power transmission for the CLPT *** designed system can transfer more than 400 W electrical power with a 2-mm gap in the EM coupler,and the efficiency was up to 90% coaxially and 87% non-coaxially in 40 MPa salt ***,a mechanical layout of a 400 W EM coupler for the underwater application in 4000-m deep sea was proposed.

关键词： Contactless power transmission(CLPT) EM coupler Deep sea Gap effects