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A general solution for Stokes flow and its application to the problem of a rigid plate translating in a fluid

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Acta Mechanica Sinica 2015年第1期31卷 32-44页

作者： Xiang-Yu Li Si-cong ren Qi-Chang He School of Mechanics and Engineering Southwest Jiaotong University School of Mechanical Engineering Southwest Jiaotong University Universit'e Paris-Est Laboratoire Mod'elisation et Simulation Multi Echelle UMR 8208 CNRS 5 Boulevard Descartes77454 Marne-la-Vall'ee France

A general solution for 3D Stokes flow is given which is different from, and more compact than the exist ing ones and more compact than them in that it involves only two scalar harmonic functions. The general solution deduced is combined with the potential theory method to study the Stokes flow induced by a rigid plate of arbitrary shape trans lating along the direction normal to it in an unbounded fluid. The boundary integral equation governing this problem is derived. When the plate is elliptic, exact analytical results are obtained not only for the drag force but also for the ve locity distributions. These results include and complete the ones available for a circular plate. Numerical examples are provided to illustrate the main results for circular and ellip tic plates. In particular, the elliptic eccentricity of a plate is shown to exhibit significant influences.

关键词： Stokes flow 3D general solutions Potentialtheory method Circular plate Elliptic plate

Pilose antler aqueous extract promotes the proliferation and osteogenic differentiation of bone marrow mesenchymal stem cells by stimulating the BMP-2/Smad1, 5/Runx2 signaling pathway

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Chinese Journal of Natural Medicines 2019年第10期17卷 756-767页

作者： ren cong GONG Wei LI Feng XIE Ming School of Pharmacy L iaoning University of Traditional Chinese MedicineDalian 116600China Affiliated Hospital of Liaoning University of Traditional Chinese Medicine Shenyang 110032China

Peptides from Pilose antler aqueous extract(PAAE) have been shown to stimulate the proliferation and differentiation of bone marrow mesenchymal stem cells(BMSCs). However, the underlying molecular mechanisms are not well understood. Here, PAAE was isolated and purified to explore the molecular mechanisms underlying PAAE’s effects on BMSCs as well as its osteoprotective effects in ovariectomized rats. Our results showed that PAAE promoted proliferation and differentiation of BMSCs to become osteoblasts by enhancing ALP activity and increasing extracellular matrix mineralization. The trabecular microarchitecture of ovariectomized rats was also found to be protected by PAAE. Quantitative reverse transcription-polymerase chain reaction(Quantitative RT-PCR) results suggest that PAAE also increased the expression of osteogenic markers including, alkaline phosphatase(ALP), runt-related transcription factor 2(Runx2), osteocalcin(OCN), bone morphogenetic protein-2(BMP-2), and collagen I(COL-I). Immunoblotting results indicated that PAAE upregulated the levels of BMP-2 and Runx2 and was associated with Smad1/5 phosphorylation. PAAE A at the concentration of 200μg·mL^-1 showed the strongest effect on proliferation and osteogenic differentiation of BMSCs after 48 h. Using matrix-assisted laser desorption/ionization time of flight mass spectrometry(MALDI-TOF MS), we identified the molecular weight of PAAE A and found that it is less than 3000 Da and showed several significant peaks. In conclusion, PAAE activates the BMP-2/Smad1, 5/Runx2 pathway to induce osteoblastic differentiation and mineralization in BMSCs and can inhibit OVX-induced bone loss. These mechanisms are likely responsible for its therapeutic effect on postmenopausal osteoporosis.

关键词： Pilose antler Postmenopausal osteoporosis Bone marrow mesenchymal stem cells BMP-2/Smad1,5/Runx2 signaling pathway

H_(3)PO_(4) activated biochars derived from different agricultural biomasses for the removal of ciprofloxacin from aqueous solution

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Particuology 2023年第4期75卷 217-227页

作者： Jinbo Ouyang Jian Chen Wenqian Chen Limin Zhou Di Cai cong ren Jiangxi Province Key Laboratory of Polymer Micro/Nano Manufacturing and Devices East China University of TechnologyNanchang330013China Department of Pharmacy National University of Singapore117544Singapore National Energy Research and Development Center for Biorefinery Beijing University of Chemical TechnologyBeijing100029China

Biochars were prepared by the pyrolysis of various H_(3)PO_(4) activated agricultural biomasses at 600℃and subsequently used as adsorbents for the removal of ciprofloxacin(CIP)from aqueous *** shell-based biochar(PSBC),corncob-based biochar(CCBC)and cotton-based biochar(CTBC)had high surface areas(571.0-1006.3 m^(2)/g),well-developed pore structures(mesopores with large pore volumes)and available adsorption functional groups(C=C,C-N and C-O-C).The CIP adsorption onto the biochars was investigated by batch experiments(kinetics,isotherms,thermodynamics,pH,etc.).Thermodynamics calculations showed the spontaneous(ΔG^(θ)0)nature of the *** particular,CCBC exhibited high adsorption capacity(120.6 mg/g)of CIP in real lake water and it also had significant removal efficiency of other common pharmaceutical contaminants from real lake environ-ment,and even in a coexisting quintuple ***,multiple interaction mechanisms of CIP adsorption onto aromatized biochar were explored combining characterization analysis and theoretical *** of the mechanism of CIP adsorption onto biochar provides new insights into the assessment of the removal of pharmaceuticals from the aqueous environment.

关键词： Biochar Adsorption Pharmaceutical contaminants Ciprofloxacin Water remediation

2,5-Diformylfuran production by photocatalytic selective oxidation of 5-hydroxymethylfurfural in water using MoS_(2)/CdIn_(2)S_(4) flower-like heterojunctions

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Chinese Journal of Chemical Engineering 2023年第2期54卷 180-191页

作者： Qian Zhu Yan Zhuang Hongqing Zhao Peng Zhan cong ren Changsheng Su Wenqiang ren Jiawen Zhang Di Cai Peiyong Qin National Energy R&D Center for Biorefinery Beijing University of Chemical TechnologyBeijing 100029China Collage of Life Science and Technology Beijing University of Chemical TechnologyBeijing 100029China Research Center for Eco-environmental Sciences Chinese Academy of ScienceBeijing 100085China

The selective oxidation of 5-hydroxymethylfurfural(HMF) into 2,5-diformylfuran(DFF) is an important reaction for renewable biomass building blocks. Compared with thermal catalytic processes, photocatalytic production of DFF from HMF has attracted tremendous attention. Herein, the MoS_(2)/CdIn_(2)S_(4)(MC)flower-like heterojunctions were prepared and considered as photocatalysts for selective oxidation of HMF into DFF under visible-light irradiation in aqueous solution. Results demonstrated MoS_(2) in MC heterojunction could promote the separation of photoexcited electron-hole pairs, while the amount of MoS_(2) dropping was proved influenced on the photocatalytic performance. 80.93% of DFF selectivity was realized when using 12.5% MC as photocatalyst. In addition, the MC catalyst also showed great potential in transformation of other biomass derived benzyl-and furyl-alcohols. The catalytic mechanism suggested that ·O_(2)^(-) was the decisive active radical for HMF oxidation. Therefore, the MC heterojunction could be applied in photocatalytic conversion of biomass to valuable chemicals under ambient condition.

关键词： 2 5-Diformylfuran(DFF) Photocatalysis MoS_(2)/CdIn_(2)S_(4)(MC) Selective oxidation Visible light irradiation

Ultrathin polyamide nanofiltration membrane prepared by triazine-based porous organic polymer as interlayer for dye removal

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Chinese Journal of Chemical Engineering 2023年第5期57卷 193-201页

作者： Yongbo Liu Zhihao Si cong ren Hanzhu Wu Peng Zhan Yuqing Peng Peiyong Qin National Energy R&D Center for Biorefinery Beijing University of Chemical TechnologyBeijing 100029China College of Life Science and Technology Beijing University of Chemical TechnologyBeijing 100029China Beijing Key Laboratory of Membrane Science and Technology College of ChemicalEngineeringBeijing University of Chemical TechnologyBeijing 100029China

Separation membrane with high flux is generally encouraged in industrial application,because of the tremendous needs for decreasing membrane areas,usage costs and space *** most effective and direct method for obtaining the high flux is to decrease membrane ***(PA)nanofiltration membrane is conventionally prepared by the direct interfacial polymerization(IP)on substrate surface,and results in a thick PA *** this work,we proposed a strategy that constructing triazine-based porous organic polymer(TRZ-POP)as the interlayer to prepare the ultrathin PA nanofiltration ***-POP is firstly deposited on the polyethersulfone substrate,and then the formed TRZ-POP provides more adhesion sites towards PA based on its high specific surface *** chemical bonding between terminal amine group of TRZ-POP and the amide group of PA further improves the binding force,and strengthens the stability of PA *** importantly,the high porosity of TRZPOP layer causes the higher polymerization of initial PA owning to the stored sufficient amino monomer;and H-bonding interaction between amine groups of TRZ-POP and piperazine(PIP)can astrict the release of ***,IP process is controlled,and the thinnest thickness of prepared PA layer is only<15 *** expected,PA/TRZ-POP membrane shows a more excellent water flux of 1414 L·m^(-2)·h^(-1)·MPa^(-1)than that of the state-of-the-art nanofiltration membranes,and without sacrificing dye *** build of TRZPOP interlayer develops a new method for obtaining a high-flux nanofiltration membrane.

关键词： Polyamide Nanofiltration Interfacial polymerization Triazine-based porous organic polymer

Promoting catalysis activity with optimizable self-generated Co-Fe alloy nanoparticles for efficient CO_(2)electrolysis performance upgrade

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Nano Research 2023年第8期16卷 10992-10999页

作者： Kun Zhang Dong Zhang Yao Wang Yihang Li cong ren Mingyue Ding Tong Liu Key Laboratory of Hydraulic Machinery Transients(Wuhan University) Ministry of EducationSchool of Power and Mechanical EngineeringThe Institute of Technological SciencesWuhan UniversityWuhan 430072China Key Laboratory of Green Chemical Process of Ministry of Education Hubei Key Laboratory of Novel Reactor and Green Chemical TechnologySchool of Chemical Engineering and PharmacyWuhan Institute of TechnologyWuhan 430205China Interdisciplinary Research Center of Smart Sensors Academy of Advanced Interdisciplinary ResearchXidian UniversityXi’an 710071China Department of Applied Chemistry School of Advanced Materials and NanotechnologyXidian UniversityXi’an 710071China

Stable and flexible metal nanoparticles(NPs)with regeneration ability are critical for long-term operation of solid oxide electrolysis cells(SOECs).Herein,a novel perovskite electrode with stoichiometric Pr_(0.4)Sr_(0.6)Co_(0.125)Fe_(0.75)Mo_(0.125)O_(3)−δ(PSFCM)is synthesized and studied,which undergoes multiple redox cycles to validate its structural stability and NPs *** Co-Fe alloy has exsolved from the parent bulk under reducing atmosphere,and is capable of reincorporation into the parent oxide after re-oxidation *** the redox process,we successfully manipulate the size and population density of the exsolved NPs,and find that the average particle size significantly reduces but the population density increases *** electrode polarization resistance of the symmetric cell remains stable for 450 h,and even activates after the redox cycling,which may be attributed to the higher quantity and larger specific surface area of the regenerated Co-Fe alloy ***,the electrochemical performance towards carbon dioxide reduction reaction(CO_(2)RR)is evaluated,and the CO_(2)electrolyzer consisting of CoFe@PSCFM-Ce_(0.8)Sm_(0.2)O_(1.9)(SDC)dual-phase electrode exhibits an excellent current density of 1.42 A·cm^(−2)at 1.6 V,which reaches 1.7 times higher than 0.83 A·cm^(−2)for the pristine PSCFM ***,with this flexible and reversible high-performance SOEC cathode material,new options and perspectives are provided for the efficient and durable CO_(2)electrolysis.

关键词： redox stability in situ exsolution regeneration carbon dioxide reduction reaction perovskite

Implant site development using titanium plate and platelet-rich fibrin for congenitally missed maxillary lateral incisors:A case report

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World Journal of Clinical Cases 2022年第6期10卷 2015-2022页

作者： Tian-Shou Zhang Mahmoud Mudalal Si-cong ren Yan-Min Zhou Department of Prosthodontics School and Hospital of StomatologyJilin UniversityChangchun 130021Jilin ProvinceChina Department of Dental Implantology School and Hospital of StomatologyJilin UniversityChangchun 130021Jilin ProvinceChina Department of Oral and Maxillofacial Surgery and Periodontology Faculty of DentistryThe Arab American UniversityJenin 240Palestine

BACKGROUND Bone deficiency and soft tissue atrophy in the absence of maxillary lateral incisors are among the most challenging problems for implant *** bone grafting is the gold standard for bone augmentation,but not without ***-rich fibrin(PRF),a biodegradable autologous biomaterial,has been widely used for bone and soft tissue ***,titanium plate is an advantageous barrier due to its good space-maintaining ***,there is a lack of literature on implant site development using titanium plate and PRF for congenitally missing maxillary lateral *** SUMMARY The patient was a 19-year-old girl with a congenitally missing tooth(#12).She underwent implant placement and simultaneous autologous bone grafting with titanium plate and *** the follow-up visit 15 d post-procedure,the vascularization of soft tissue was *** was no swelling or pain after the *** months postoperatively,bone regeneration was ***,the definitive restoration was placed,and the patient was satisfied with the esthetic *** Implant site development using titanium plate and PRF for congenitally missing maxillary lateral incisors is a feasible *** this case,the labial bone plate was displaced but remained connected to the base bone,ensuring blood *** titanium plate fixed the labial bone plate and maintained the osteogenic space,while the PRF provided growth factors and leukocytes for bone and soft tissue ***,the procedure reduced the surgical complexity and adverse reactions,displaying outstanding esthetic outcomes.

关键词： Implant placement Platelet-rich fibrin Missing incisor Bone augmentation Soft tissue regeneration Case report

Determination of particle size distribution by multi-scale analysis of acoustic emission signals in gas-solid fluidized bed

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第4期12卷 260-267页

作者： cong-jing ren Jing-dai WANG Di SONG Bin-bo JIANG Zu-wei LIAO Yong-rong YANG State Key Laboratory of Chemical Engineering Department of Chemical and Biochemical Engineering Zhejiang University Hangzhou 310027 China

Particle size distribution(PSD) is an important parameter in the process of fluidization,and it always plays a crucial role in a gas-solid fluidized system.A PSD model for on-line PSD determination based on acoustic emission(AE) measurement was developed according to the mechanism of particle collision with the inner wall of the cylinder and multi-scale wavelet decomposition *** PSD model illuminates the quantitative relationship between the energy percentage of AE signals for different scales and the PSD,which indicates the feasibility of the application of the PSD *** were undertaken both in lab and plant gas-solid fluidized setup with polyethylene particles,and the parameters of the PSD model were calibrated and *** experimental conditions and results proved that the PSD model was suitable for on-line measurement and was sufficiently sensible and *** agglomeration,the PSD model also showed exact serviceability on detecting the onset of agglomeration by abnormal PSD,and the result agreed with that from the radiation ***,AE measurement was found to be a reliable and credible means for understanding the PSD information that affects the behavior of a system,which can provide valuable guidance for practical applications.

关键词： Particle size distribution(PSD) Acoustic emission(AE) Fluidized bed Multi-scale Agglomeration

Characterization and Wettability of ZnO Film Prepared by Chemical Etching Method

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Chemical Research in Chinese Universities 2013年第2期29卷 333-337页

作者： GUO Hua-xi JIA Hui-ying ZENG Jian-bo cong Qian ren Lu-quan Key Laboratory of Bionic Engineering Ministry of Education Jilin University Changchun 130025 P. R. China

ZnO thin films were prepared by a chemical etching method and their wettability was investigated. The structure and surface composition structure were characterized by means of scanning electron microscopy, X-ray photoelectronic spectrometry（XPS）, X-ray diffraction（XRD） and Raman spectrometry. These analyses reveal that the etched films were large-scale micro-nanohierarchical structures composed of a Zn core and a ZnO coating. Superhy- drophobic surfaces with water contact angles of over 150~ were obtained by n-octadecanethiol（ODT） modification. The XPS and Raman results indicate that ODT molecules were bound to the ZnO surface with the S head group by forming Zn--S bond.

关键词： ZnO Chemical etching Micro-nanostructure Raman spectrometry Wettability