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Effect of Aging Temperature on Erosion-Corrosion Behavior of 17-4PH Stainless Steels in Dilute Sulphuric Acid Slurry

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Journal of Iron and Steel Research International 2006年第5期13卷 73-78页

作者： li ping CAI Qi-zhou WEI Bo-kang ZHANG Xian-zhong State Key Lab of Plastic Forming Simulation and Dies/Mould Technology Huazhong University of Science and Technology Wuhan 430074 Hubei China

The effect of aging temperature on erosion corrosion （E-C） behavior of 17-4PH stainless steels in dilute sulphuric acid slurry containing solid particles was studied by using self-made rotating E-C apparatus. The effect of impact velocity on EC behavior of 17 4PH steels at different aging temperatures was analyzed. Surface micrographs of the specimens after E C test were observed by using scanning electron microscope （SEM）. The results showed that under the condition of the same solution heat treatment, when aging temperature ranged from 400 ℃ to 610℃, the hardness reached the highest value near the temperature 460℃. The characteristics of E-C for 17-4PH stainless steels at different aging temperatures were as follows： pure erosion （wear） was dominant, corrosion was subordinate and at the same time corrosion promoted erosion. The effect of aging temperature on E-C rate of 17-4PH steels was not significant at low impact velocity, but it was found that E-C resistance of 17-4PH steels aged near 460℃ was the most excellent due to the best precipitation strengthening effect of fine and dispersed e-Cu phase. With a prerequisite of appropriate corrosion resistance, the precipitation hardening could significantly improve the E-C resistance of the materials.

关键词： aging temperature 17-4PH precipitation-hardened stainless steel erosion-corrosion (E-C) hardness

Effect of nitrogen addition on microstructure and erosion-corrosion behavior of stainless steel in acidic slurry

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China Foundry 2009年第3期6卷 197-201页

作者： li ping Cai Qi zhou Wei Bo kang li Feng jun School of Material Science and Engineering Henan Polytechnic UniversityJiaozuo 454000HenanChina China Yituo Group Co. Ltd.Luoyang 471004HenanChina School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China China Yituo Group Co.Ltd.Luoyang 471004HenanChina

Effect of nitrogen content on the microstructure and erosion-corrosion (E-C) behavior of stainless steel (containing about 25% Cr, 5%-6% Ni, and 1%-2% Mo) was investigated by using optical microscope(OM), potentiodynamic polarization curve and immersion method, a self-made rotating disk apparatus and scanning electron microscopy (SEM) and so on. The results show that with the increase of nitrogen content from 0 (no adding) to 0.485 wt.%, the Cr(eq)/Ni(eq) ratio of the tested materials decreases from 4.14 to 1.23 and the ferrite volume percentage of the steel tested linearly decreases approximately from 90% to 10%. The effect of nitrogen content on polarization behavior of the studied steel was not significant. All the passive current densities (I(p)) and pure corrosion rates (V(c)) of the different N content specimens in the acidic solution (slurry containing 0.1 M H(2)SO(4)+0.06% Cl(-)+0.4% F(-), the simplified zinc hydrometallurgy slurry) are too low and nearly negligible. Whereas the pure erosion rates (V(e)) of the four scenarios of the steels tested (N content, wt.%: N1, no adding; N2, 0.143%; N3, 0.289%; N4, 0485%, respectively) are much higher than their V(c) values. The V(e) values of the tested steels are in the order of N4 > N1 > N3 > N2, at the same time, the total weight loss rates (V(t)) follow the order of N4 > N1 > N3 > N2, too. N2 steel consisting of approximately equal volume fractions of ferrite (alpha) and austenite (gamma) exhibits the most excellent E-C resistance and erosion resistance, while the stainless steels possessing the big difference between alpha phase and gamma phase, such as N1 steel nearly possessing single ferrite or N4 steel nearly possessing single austenite, show poorer E-C resistance and erosion resistance.

关键词： nitrogen microstructure erosion-corrosion (E-C) duplex stainless steels

New indicators in evaluation of hemolysis,elevated liver enzymes,and low platelet syndrome:A case-control study

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World Journal of Clinical Cases 2021年第6期9卷 1259-1270页

作者： Su-Ya Kang Yun Wang li-ping zhou Hong Zhang Department of Obstetrics Suzhou Affiliated Hospital of Nanjing Medical UniversitySuzhou Municipal HospitalSuzhou 215002Jiangsu ProvinceChina Department of Gynecology and Obstetrics The Second Affiliated Hospital of Soochow UniversitySuzhou 215004Jiangsu ProvinceChina

BACKGROUND Indices such as the neutrophil-to-lymphocyte ratio(NLR),platelet-to-lymphocyte ratio(PLR),mean platelet volume(MPV),platelet distribution width(PDW),and red cell distribution width(RDW)are considered new markers of the systemic inflammatory response(SIR),and have been widely implemented for the diagnosis of patients with inflammatory *** new indicators have also been widely investigated in preeclampsia(PE)but less analyzed in hemolysis,elevated liver enzymes,and low platelet(HELLP)*** To compare SIR markers among HELLP patients,PE only patients,and healthy *** This retrospective case-control study enrolled 630 cases,including 210 patients with HELLP syndrome(HELLP group),210 patients with only PE(PE group)and 210 healthy gravidae(control group).The three groups were matched by age,parity,status of assisted reproduction,and multiple ***,gestational age at complete blood count collection,gestational age at delivery,mode of delivery,*** *** main indices as NLR,PLR,MPV,PDW,and RDW among the groups were compared,as well as some secondary outcomes including neutrophil,platelets,and *** The NLR(6.4 vs 4.3 vs 3.5),MPV(11.9 vs 11.2 vs 10.7),PDW(16.4 vs 13.3 vs 14.2),leukocyte(12.4×10^(9)/L vs 9.7×10^(9)/L vs 8.7×10^(9)/L)and neutrophil count(9.9×10^(9)/L vs 7.3×10^(9)/L vs 6.1×10^(9)/L)were highest in the HELLP group,lower in the PE group,and lowest in the control *** the overall comparisons between the three groups(all bPlicited statistically significant differences(all dP<0.01,except control vs PE:cP<0.05 in PDW).The average lymphocyte counts were 1.4(1.1,2.0)×10^(9)/L in the HELLP group,1.6(1.3,2.0)×10^(9)/L in the PE group and 1.7(1.4,2.0)×10^(9)/L in the control *** overall comparison of lymphocyte count within the three groups had statistically significant differences(P=0.000).The pairwise comparisons between

关键词： Hemolysis,elevated liver enzymes,and low platelet syndrome Neutrophil-tolymphocyte ratio Platelet-to-lymphocyte ratio Mean platelet volume Platelet distribution width Red cell distribution width

Nonlinear Coupled Analysis of a Single Point Mooring System

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Journal of Ocean University of China 2007年第3期6卷 310-314页

作者： WANG Junrong li Huajun li ping zhou Kai Coastal and Offshore Engineering Institute Ocean University of China Qingdao 266071 P.R. China

Coupled effects on a single point mooring(SPM) system subjected to the combined action of wind,waves and current are studied in this paper. Due to the complicatedness of the sea state and the huge size of the vessel,physical experimental study is both time consuming and uneconomical,whereas the numerical study is cost-effective and DNV software provides powerful SESAM software in solving the issues. This paper focuses on the modeling process of the SPM system,catenary equilibrium calculation,static analysis of the vessel in three different scenarios,and dynamic response simulation of the SPM system under environmental excitations. The three scenarios in study are as follows:the SPM is under the combined function of(a) wind,waves and current,(b) wind and waves,(c) current and waves. They are so set that one can compare the contributions of different types of loads in both static and dynamic studies. Numerical study shows that wind and current are the two major factors contributing to the mooring line tension,and surge and sway are the two dominant motions of the moored vessel subjected to environmental excitations.

关键词： single point mooring system response amplitude operator catenary equilibrium static analysis dynamic response

Determination of soluble solid content and acidity of loquats based on FT-NIR spectroscopy

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2009年第2期10卷 120-125页

作者： Xia-ping FU Jian-ping li Ying zhou Yi-bin YING li-juan XIE Xiao-ying NIU Zhan-ke YAN Hai-yan YU College of Biosystem Engineering and Food Science Zhejiang University Hangzhou 310029 China

The near infrared （NIR） spectroscopy technique has been applied in many fields because of its advantages of simple preparation, fast response, and non-destructiveness. We investigated the potential of NIR spectroscopy in diffuse reflectance mode for determining the soluble solid content （SSC） and acidity （pH） of intact loquats. Two cultivars of loquats （Dahongpao and Jiajiaozhong） harvested from two orchards （Tangxi and Chun＇an, Zhejiang, China） were used for the measurement of NIR spectra between 800 and 2500 nm. A total of 400 loquats （100 samples of each cultivar from each orchard） were used in this study. Relationships between NIR spectra and SSC and acidity of loquats were evaluated using partial least square （PLS） method. Spectra preprocessing options included the first and second derivatives, multiple scatter correction （MSC）, and the standard normal variate （SNV）. Three separate spectral windows identified as full NIR （800-2500 nm）, short NIR （800-1100 rim）, and long NIR （1100-2500 nm） were studied in factorial combination with the preprocessing options. The models gave relatively good predictions of the SSC of loquats, with root mean square error of prediction （RMSEP） values of 1.21, 1.00, 0.965, and 1.16 °Brix for Tangxi-Dahongpao, Tangxi-Jiajiaozhong, Chun＇an-Dahongpao, and Chun＇an-Jiajiaozhong, respectively. The acidity prediction was not satisfactory, with the RMSEP of 0.382, 0.194, 0.388, and 0.361 for the above four loquats, respectively. The results indicate that NIR diffuse reflectance spectroscopy can be used to predict the SSC and acidity of loquat fruit.

关键词： Near infrared (NIR) spectroscopy Loquats Soluble solid content (SSC) Acidity Partial least square (PLS) Modeling Spectra preprocessing

Polydopamine-modified chitin conduits with sustained release of bioactive peptides enhance peripheral nerve regeneration in rats

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Neural Regeneration Research 2022年第11期17卷 2544-2550页

作者： Ci li Song-Yang liu li-ping zhou Tian-Tian Min Meng Zhang Wei Pi Yong-Qiang Wen Pei-Xun Zhang Department of Orthopedics and Trauma Peking University People’s HospitalBeijingChina Key Laboratory of Trauma and Neural Regeneration Ministry of EducationBeijingChina National Center for Trauma Medicine BeijingChina Beijing Key Laboratory for Bioengineering and Sensing Technology School of Chemistry and Biological EngineeringUniversity of Science and Technology BeijingBeijingChina

The introduction of neurotrophic factors into injured peripheral nerve sites is beneficial to peripheral nerve ***,neurotrophic facto rs are rapidly degraded in vivo and obstruct axonal regeneration when used at a supraphysiological dose,which limits their clinical *** mimetic peptides have been developed to be used in place of neurotrophic factors because they have a similar mode of action to the original growth fa ctors and can activate the equivalent receptors but have simplified sequences and *** this study,we created polydopamine-modified chitin conduits loaded with brain-derived neurotrophic factor mimetic peptides and vascular endothelial growth fa ctor mimetic peptides(Chi/PDA-Ps).We found that the Chi/PDA-Ps conduits were less cytotoxic in vitro than chitin conduits alone and provided sustained release of functional *** this study,we evaluated the biocompatibility of the Chi/P DA-Ps ***-derived neurotrophic factor mimetic peptide and vascular endothelial growth fa ctor mimetic peptide synergistically promoted prolife ration of Schwann cells and secretion of neurotrophic factors by Schwann cells and attachment and migration of endothelial cells in *** Chi/P DA-Ps conduits were used to bridge a 2 mm gap between the nerve stumps in rat models of sciatic nerve *** found that the application of Chi/PDA-Ps conduits could improve the motor function of rats and reduce gastrocnemius *** electrophysiological results and the microstructure of regenerative nerves showed that the nerve conduction function and re myelination was further resto *** findings suggest that the Chi/PDA-Ps conduits have great potential in peripheral nerve injury repair.

关键词： angiogenesis bioactive peptides nerve repair neurotrophic factor peripheral nerve injury peripheral nerve regeneration polydopamine surface modification synergistic effects tissue engineering

Genetic insight of the H5N1 hemagglutinin cleavage site

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Chinese Science Bulletin 2007年第17期52卷 2374-2379页

作者： GUO Xiaoli ZHU YiSheng li YiXue SHI ping zhou HaoKui YAO JinSong HUANG ZhenDe WEI DongQing College of life Sciences and Biotechnology Shanghai Jiao Tong University Shanghai 200240 China

The cleavability of the hemagglutinin (HA) plays a major role in virulence of avian influenza viruses. Detailed analyses of the cleavage sequences and their evolution would give insights into the high pathogenicity of the H5N1 virus. HA segments were visually identifiable in the cellular automata (CA) image, and a feature gene segment (FGS) was only found in H5N1 rather than any other subtype. This FGS is a 30-bp gene segment mainly consisting of ‘A’ and ‘G’. When translated into amino acids the FGS converted into a sequence of mainly basic amino acids with positive charges. This feature amino acid segment (FAAS) was located in the cleavage site loop of HA which was potentially cleavable by various proteases. The 3D structure of H5N1 HA was reconstructed using homology modelling. It was found that the cleavage site loop was well exposed to potential proteases. The molecular surfaces were reconstructed to study how mutation and deletion of some amino acids in the FAAS affected the charge distribution. It was found that some mutations had severely changed the landscape of the charge dis- tribution. Statistical analyses of FAAS were made with respect to when and where the H5N1 viruses were found. In 2005, there were less un-mutated FAAS than the other years according to temporal evolution, and more mutated FAAS appeared in China than other regions according to geographic dis- tribution. These results are helpful for exploring the evolution of virus high pathogenicity.

关键词：红血球凝聚素 H5N1病毒分裂点细胞自动机

Some Results on the Cardinalities of Row Space of Boolean Matrices

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Chinese Quarterly Journal of Mathematics 2008年第4期23卷 582-588页

作者： ZHONG li-ping zhou Jian-hui Mathematics and Computational Science School Zhanjiang Normal University Zhanjiang 524048 China

Let Bn be the set of all n×n Boolean Matrices; R（A） denote the row space of A∈Bn, ｜R（A）｜ denote the cardinality of R（A）, m, n, k, l, t, i, γi be positive integers, Si, λi be non negative integers. In this paper, we prove the following two results：（1）Let n≥13,n-3≥k〉Sl,Si＋〉Si,i=1,2…,*** k＋l≤n,then for any m=2^k＋2^S1-l＋…＋2^S1,there exists A∈Bn,such that ｜R（A）｜=m.（2）Let n≥13,n-3≥k〉Sn-k-1〉Sn-k-2〉…S1〉λt〉λt-1〉…〉λ1,2≤t≤*** exist γi（k＋1≤γi≤n-1,i=1,2…,t-1）γi〈γi＋1 and λt-λt-1≤k-Sn-γ1,λt-i-λt-i-1≤Sn-γi-Sn-γii＋1,i=1,2…,t-2,then for any m=2^k＋2^Sn-k-1＋2^Sn-k-1＋2^Sn-k-2＋…＋2^S1＋2^λt＋2^λt-1…＋2^λ1,there exists A∈Bn,as such that ｜R（A）｜=m.

关键词： Boolean matrix row space cardinality of a row space

Melittin analog p5RHH enhances recombinant adeno-associated virus transduction efficiency

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Journal of Integrative Medicine 2024年第1期22卷 72-82页

作者： Jing-shun Meng Yun He Heng-bin Yang li-ping zhou Si-yuan Wang Xi-lin Feng Omar Yahya Al-shargi Xiao-min Yu li-qing Zhu Chang-quan ling Shanghai University of Traditional Chinese Medicine Shanghai 201203China Oncology Department of Traditional Chinese Medicine Changhai HospitalNaval Medical UniversityShanghai 200433China Faculty of Traditional Chinese Medicine Naval Medical UniversityShanghai 200043China State Key Laboratory of Genetic Engineering and Engineering Research Center of Gene Technology(Ministry of Education) School of Life SciencesZhongshan HospitalFudan UniversityShanghai 200438China Yantai Fuheng Biological Technology Co. Ltd.YantaiShandong Province 264006China. Department of Clinical Laboratory the First Affiliated Hospital of Wenzhou Medical UniversityWenzhou 325000Zhejiang ProvinceChina

Objective Melittin and its derivatives have been characterized to establish effective gene delivery *** capability of facilitating endosomal release enhances the nanoparticles-based gene ***,little investigation has been conducted to explore its potential application in the context of viral *** Various melittin-derived peptides were inserted into the loop VIII of the capsid proteins of recombinant adeno-associated virus *** vectors carrying either gfp or fluc genes were subjected to qPCR assays and transduction assays of HEK293T cells to investigate the efficiency of vector production and gene *** addition,the ability of a specific p5RHH-rAAV vector to deliver genes was examined through in vitro transduction of different cultured cells and in vivo tail vein administration to C57BL/6 ***,the intricate details of the vector-mediated transduction mechanisms were revealed by specific pharmacological inhibitors of every stage of the rAAV2 intracellular life *** A total of 76 melittin-related peptides were compiled from existing *** them,cMA2,Melt13,p5RHH and aAR3 were found to significantly enhance the gene delivery efficiency of rAAV2 *** p5RHH-rAAV2 vectors efficiently transduced not only rAAV-potent cell lines but also cell lines previously considered resistant to ***,bafilomycin A1,a vacuolar endosome acidification inhibitor,completely inhibited the transgene expression mediated by the p5RHH-rAAV2 *** importantly,p5RHH-rAAV8 vectors also demonstrated increased hepatic transduction in vivo in C57BL/6 *** The incorporation of melittin analogues into the rAAV capsids results in a significant improvement in rAAV-mediated transgene *** further modifications remain an area of interest,our studies have substantially broadened the pharmacological prospects of melittin in the context of viral vector-mediated gene delivery.

关键词： Melittin Recombinant adeno-associated virus Capsid engineering Transduction efficiency