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Electrokinetic pumping system based on nanochannel membrane for liquid delivery

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Chinese Chemical Letters 2007年第3期18卷 352-354页

作者： ling Xin chen Qing ling Li Xiao Lei Wang Hai Long Wang ya feng guan College of Chemistry Chemical Engineering and Materials Science Shandong Normal University Jinan 250014 China Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 China

Nonmechanical pumping of liquids is of key importance for applications from the biomedical microfluidic chip to drug delivery systems. In this paper, a new electrokinetic pump （EOP） system with polycarbonate nanoehannel membrane sandwiched between two membrane holders was constructed. The pump was tested with water and phosphate buffer at 1-6 V applied voltage, the maximum pressure and flow rate are 0.32 MPa （3.2 atm） and 4.2 μL/min for phosphate buffer, respectively. This proof-of-concept pump shows its potential use for drugs or chemical agents delivery by the usage of different membrane materials.

关键词： Electrokinetic pump Electroosmotic pump Nanochannel Microfluidic chip μTAS

Determination of Magnolol and Honokiol by Non-aqueous Capillary Electrophoresis

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Chemical Research in Chinese Universities 2006年第3期22卷 335-338页

作者： TIAN Yi-ling chen guan-hua College of Life Science Agricultural University of Hebei Baoding 071001 P. R. China College of Food Science ＆ Technology Agricultural University of Hebei Baoding 071001 P. R. China

Two active principles in traditional Chinese medicine Magnolia officinalis, magnolol and honokiol, were successfully separated by means of nonaqueous capillary electrophoresis. The effect of the composition of a nonaqueous buffer on column efficiency and resolution, and the effect of acid additives on peak shapes were researched. The separation was conducted with a running buffer in a mixture of methanol/aeetonitrile/formamide （ volume ratio ： 1 ： 2 ： 2 ）, in which the concentrations of Tris, acetic acid, and water were 60 retool/L, 0. 04 mmol/L and 5% （ volume fration）, respectively, and the pH^＊（apperent pH） of the running buffer was 8.96. Magnolol and honokiol were separated on baseline within 20 min. The relative standard deviation of the analytes＇ concentrations in the sample is 1.32% for magnolol and 1.60% for honokiol, and the recoveries of the spiked sample are 98.4% for magnolol and 98. 0% for honokiol, respectively.

关键词： Nonaqueous capillary electrophoresis Magnolol Honokiol

Transformation and separation of metallic iron in reduced ilmenite during corrosion process

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Journal of Iron and Steel Research International 2020年第12期27卷 1372-1381页

作者： Fu-qiang Zheng Xia Liu Yu-feng Guo Shuai Wang feng chen ling-zhi yang Tao Jiang guan-zhou Qiu School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083HunanChina Hunan Qingzhiyuan Environmental Protection Technology Co. Ltd.Changsha 410083HunanChina

The effects of corrosion temperature, oxygen flow rate and corrosion time on the transformation of metallic iron were systematically studied, and the effects of mineral phases of Fe-bearing products on Ti-Fe separation were investigated. The reaction mechanism of metallic iron in corrosion process was proposed. The results showed that corrosion temperature played a key role in determining the transformation of metallic iron in reduced ilmenite during corrosion process. Under suitable corrosion conditions, Fe-bearing mineral in reduced ilmenite could be converted to amorphous ferric hydroxide, lepidocrocite,hematite and magnetite, respectively, and lepidocrocite was the most easily separated Fe-bearing mineral from corrosion products owing to the significant density difference between lepidocrocite and Ti-rich materials. The Ti-rich material with 77.81 wt.% TiO2 and Fe-bearing product with 52.69 wt.% total Fe were obtained by gravity separation. The Ti recovery ratio and Fe recovery ratio were 91.16% and 86.27%, respectively.

关键词： Reduced ilmenite Corrosion Ti-rich material Fe-bearing mineral Lepidocrocite Metallic iron

The miR319-Targeted GhTCP4 Promotes the Transition from Cell Elongation to Wall Thickening in Cotton Fiber

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Molecular Plant 2020年第7期13卷 1063-1077页

作者： Jun-feng Cao Bo Zhao Chao-chen Huang Zhi-Wen chen Ting Zhao Hong-Ru Liu guan-Jing Hu Xiao-Xia Shangguan Chun-Min Shan- ling-Jian Wang Tian-Zhen Zhang Jonathan F.Wendel Xue-Ying guan Xiao-ya chen National Key Laboratory of Plant Molecular Genetics Institute of Plant Physiology and Ecology/CAS Center for Excellence in Molecular Plant SciencesChinese Academy of SciencesShanghai 200032China Plant Stress Biology Center Institute of Plant Physiology and Ecology/CAS Center for Excellence in Molecular Plant SciencesChinese Academy of SciencesShanghai 200032China University of Chinese Academy of Sciences Shanghai 200032China School of Life Science and Technology ShanghaiTech UniversityShanghai 201210China Agronomy Department College of Agriculture and BiotechnologyZhejiang UniversityHangzhouZhejiang 310058China Department of Ecology Evolution and Organismal BiologyIowa State UniversityAmesIA 50011.USA Plant Science Research Center Shanghai Key Laboratory of Plant Functional Genomics and ResourcesShanghai Chenshan Botanical GardenShanghai 201602China

Plant cell growth involves a complex interplay among cell-wall expansion, biosynthesis, and, in specific tissues, secondary cell wall (SCW) deposition, yet the coordination of these processes remains elusive. Cotton fiber cells are developmentally synchronous, highly elongated, and contain nearly pure cellulose when mature. Here, we report that the transcription factor GhTCP4 plays an important role in balancing cotton fiber cell elongation and wall synthesis. During fiber development the expression of miR319 declines while GhTCP4 transcript levels increase, with high levels of the latter promoting SCW deposition. GhTCP4 interacts with a homeobox-containing factor, GhHOX3, and repressing its transcriptional activity. GhTCP4 and GhHOX3 function antagonistically to regulate cell elongation, thereby establishing temporal control of fiber cell transition to the SCW stage. We found that overexpression of GhTCP4A upregulated and accelerated activation of the SCW biosynthetic pathway in fiber cells, as revealed by transcriptome and promoter activity analyses, resulting in shorter fibers with varied lengths and thicker walls. In contrast, GhTCP4 downregulation led to slightly longer fibers and thinner cell walls. The GhHOX3–GhTCP4 complex may represent a general mechanism of cellular development in plants since both are conserved factors in many species, thus providing us a potential molecular tool for the design of fiber traits.

关键词： cell elongation secondary cell wall cotton fiber Gossypium hirsutum TCP microRNA

Fault rupture propagation in soil with intercalation using nonlocal model and softening modulus modification

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第11期15卷 2973-2993页

作者： Jisen Shi Li guan Duanyang Zhuang Xiang chen Daosheng ling Center for Hypergravity Experiment and Interdisciplinary Research Zhejiang UniversityHangzhou310058China Department of Civil Engineering Jiaxing UniversityJiaxing314000China MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering Zhejiang UniversityHangzhou310058China

Fault rupture propagation is more complex in the overlying soil with intercalation than in homogeneous soil,and it is challenging to simulate this phenomenon accurately using the finite element *** address this issue,an improved nonlocal model that incorporates softening modulus modification is *** methodology has the advantage that the solutions are independent of both mesh sizes and characteristic lengths,while maintaining objective softening rates of *** the proposed methodology,a series of numerical simulations are conducted to investigate the effects of different mechanical parameters,such as elastic modulus,friction angle and dilation angle of the soil within the intercalation,as well as the impact of geometries,such as the depth and thickness of the intercalation,on the fault rupture *** study not only provides significant insights into the mechanisms of fault rupture propagation,specifically in relation to intercalations,but also shows a great value in promoting the current research on fault rupture.

关键词： Fault rupture Nonlocal model Mesh dependence Intercalation Numerical simulation

Oscillation properties of matter–wave bright solitons in harmonic potentials

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Chinese Physics B 2022年第8期31卷 317-324页

作者： Shu-Wen guan ling-Zheng Meng Li-chen Zhao School of Physics Northwest UniversityXi’an 710127China NSFC–SPTP Peng Huanwu Center for Fundamental Theory Xi’an 710127China Shaanxi Key Laboratory for Theoretical Physics Frontiers Xi’an 710127China

We investigate the oscillation periods of bright soliton pair or vector bright soliton pair in harmonic potentials. We demonstrate that periods of low-speed solitons are greatly affected by the position shift during their collisions. The modified oscillation periods are described by defining a characterized speed, with the aid of asymptotic analysis on related exact analytic soliton solutions in integrable cases. The oscillation period can be used to distinguish the inter-and intra-species interactions between solitons. However, a bright soliton cannot oscillate in a harmonic trap, when it is coupled with a dark soliton(without any trapping potentials). Interestingly, it can oscillate in an anti-harmonic potential, and the oscillation behavior is explained by a quasi-particle theory. The modified period of two dark-bright solitons can be also described well by the characterized speed. These results address well the effects of position shift during soliton collision, which provides an important supplement for previous studies without considering phase shift effects.

关键词： matter–wave bright soliton harmonic potential oscillation period

Formation and structure of composite coating of HDA and micro-plasma oxidation on A3 steel

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中国有色金属学会会刊：英文版 2004年第z1期14卷 310-314页

作者： YU Sheng-xue XIA Yuan chen ling guan Yong-jun yaO Mei Department of Environment Science and Chemical Engineering Yanshan University Qinhuangdao 066004 China Institute of Mechanics Chinese Academy of Science Beijing 100080 China Institute of Mechanics Chinese Academy of Science Beijing 100080 China Department of Environment Science and Chemical EngineeringYanshan University Qinhuangdao 066004 China Institute of Mechanics Chinese Academy of Science Beijing 100080 China College of Materials Science and EngineeringYanshan University Qinhuangdao 066004 China

Composite coatings were obtained on A3 steel by hot dipping aluminum(HDA) at 720 ℃ for 6 min and micro-plasma oxidation(MPO) in alkali electrolyte. The surface morphology, element distribution and interface structure of composite coatings were studied by means of XRD, SEM and EDS. The results show that the composite coatings obtained through HDA/MPO on A3 steel consist of four layers. From the surface to the substrate, the layer is loose Al2O3 ceramic, compact Al2O3 ceramic, Al and FeAl intermetallic compound layer in turn. The adhesions among all the layers are strengthened because the ceramic layer formed at the Al surface originally, FeAl intermetallic compound layer and substrate are combined in metallurgical form through mutual diffusion during HDA *** experiment results disclose that the anti-corrosion performance and wear resistance of composite coating are obviously improved through HDA/MPO treatment.

关键词： hot dipping aluminum micro-plasma oxidation composite coating ceramic coating

Genomic Epidemiology of Imported Cases of COVID-19 in guangdong Province,China,October 2020–May 2021

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Biomedical and Environmental Sciences 2022年第5期35卷 393-401页

作者： LIANG Dan WANG Tao LI Jiao Jiao guan Da Wei ZHANG guan Ting LIANG Yu feng LI An An HONG Wen Shan WANG Li chen Meng Lin DENG Xiao ling chen feng Juan PAN Xing Fei JIA Hong ling LEI Chun Liang KE Chang Wen guangdong Provincial Key Laboratory of Virology Institute of Medical MicrobiologyJinan UniversityGuangzhou 510632GuangdongChina guangzhou National Laboratory Guangzhou 510700GuangdongChina guangdong Provincial Center for disease control and prevention Guangdong Workstation for Emerging Infectious Disease Control and PreventionGuangzhou 511430GuangdongChina Shantou University Medical College Shantou 515041GuangdongChina guangzhou Eighth People’s Hospital Guangzhou 510030GuangdongChina School of public health Sun Yat-sen UniversityGuangzhou 510080GuangdongChina School of Public Health Southern Medical UniversityGuangzhou 510515GuangdongChina guangzhou Mendel Genomics and Medical Technology Co. Ltd.Guangzhou 510535GuangdongChina Department of Infectious Diseases the Third Affiliated Hospital of Guangzhou Medical UniversityGuangzhou 510150GuangdongChina Department of Medical Biochemistry and Molecular Biology School of MedicineJinan UniversityGuangzhou 510632GuangdongChina

Objective The pandemic of severe acute respiratory syndrome coronavirus 2(SARS-Co V-2) has been engendering enormous hazards to the world. We obtained the complete genome sequences of SARSCo V-2 from imported cases admitted to the guangzhou Eighth People’s Hospital, which was appointed by the guangdong provincial government to treat coronavirus disease 2019(COVID-19). The SARS-Co V-2 diversity was analyzed, and the mutation characteristics, time, and regional trend of variant emergence were *** In total, 177 throat swab samples were obtained from COVID-19 patients(from October2020 to May 2021). High-throughput sequencing technology was used to detect the viral sequences of patients infected with SARS-Co V-2. Phylogenetic and molecular evolutionary analyses were used to evaluate the mutation characteristics and the time and regional trends of *** We observed that the imported cases mainly occurred after January 2021, peaking in May2021, with the highest proportion observed from cases originating from the United States. The main lineages were found in Europe, Africa, and North America, and B.1.1.7 and B.1.351 were the two major sublineages. Sublineage B.1.618 was the Asian lineage(Indian) found in this study, and B.1.1.228 was not included in the lineage list of the Pangolin web. A reasonably high homology was observed among all samples. The total frequency of mutations showed that the open reading frame 1 a(ORF1 a) protein had the highest mutation density at the nucleotide level, and the D614 G mutation in the spike protein was the commonest at the amino acid level. Most importantly, we identified some amino acid mutations in positions S, ORF7 b, and ORF9 b, and they have neither been reported on the Global Initiative of Sharing All Influenza Data nor published in Pub Med among all missense *** These results suggested the diversity of lineages and sublineages and the high homology at the amino acid level among imported case

关键词： Severe acute respiratory syndrome coronavirus 2 Next-Generation sequencing Phylogenetic tree Variants

Characteristic Mode Analysis for Thin Dielectric Sheets with Alternative Surface Integral Equation

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Chinese Journal of Electronics 2022年第6期31卷 1181-1188页

作者： JIA Chunlai HE Zi DING Dazhi guan ling AI Xia LIU Jiaqi chen Xuewen Department of Communication Engineering Nanjing University of Science and Technology Science and Technology on Electromagnetic Scattering Laboratory Beijing Institute of Environmental Features National Key Laboratory of Science and Technology on Test Physics and Numerical Mathematics School of Physics and Wuhan National Laboratory for Optoelectronics Huazhong University of Science and Technology

When the dielectric sheet is electrically thin in the normal direction, the conventional volume integral equation(VIE) can be approximately simplified to the surface one. On this basis, a novel surface integral equation-based formulation is presented for analyzing characteristic mode(CM) of thin dielectric sheets. The resultant CMs are expressed with tangential and normal components of electric volume currents, which are more intuitive than the conventional VIE-based one. Due to the application of volume equivalence principle, the proposed formulation is immune to non-physical modes. The CMs of typical thin dielectric bodies, including the dielectric substrate and radome, are analyzed to show that the proposed formulation is computationally efficient with encouraging accuracy.

关键词： normal components alternative surface integral equation thin dielectric sheets normal direction electric volume currents dielectric sheet radome radomes dielectric bodies surface integral equation-based formulation volume equivalence principle thin dielectric bodies tangential components nonphysical modes electromagnetic wave scattering conventional volume integral equation integral equations characteristic mode analysis dielectric substrate