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Coupled extension and thickness-twist vibrations of lateral field excited AT-cut quartz plates

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Acta Mechanica Sinica 2014年第1期30卷 67-72页

作者： Ting-Feng ma Rong-Xing Wu Ji Wang Jian-Ke Du Li-Li Yuan fa-Peng Yu Chao Xie Piezoelectric Device Laboratory School of Mechanical Engineering & MechanicsNingbo University Department of Architectural Engineering Ningbo Polytechnic State Key Lab of Crystal materials and Institute of Crystal materials Shandong University

In this paper, the coupled extension and thickness- twist vibrations are studied for AT-cut quartz plates under Lateral Field Excitation （LFE） with variations along the x1- direction. Mindlin＇s two-dimensional equations are used for anisotropic crystal plates. Both free and electrically forced vibrations are considered. Important vibration characteristics are obtained, including dispersion relations, frequency spectra, and motional capacitances. It is shown that, to avoid the effects of the couplings between extension and thickness-twist vibrations, a series of discrete values of the length/thickness ratio of the crystal plate need to be excluded. The results are of fundamental significance for the design of LFE resonators and sensors.

关键词： Lateral field excitation - Resonators Quartz Thickness-twist vibrations

Cube texture formation of Ni9.3W alloy substrates:preparation by optimized deformation sequence and anneal process

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Rare Metals 2018年第8期37卷 662-667页

作者： fa-Xue Peng Hong-Li Suo Lin ma Hui Tian Min Liu Jing Liu Dan Yu Yi-Chen Meng College of materials Science and Engineering Beijing University of Technology

The Ni9.3W alloy with no ferromagnetism and high yield strength is one of the most promising textured substrate materials for coated conductors, but its low stacking fault energy makes it difficult to obtain a strong cube texture by traditional rolling methods and recrystal- lization anneals. This paper introduces four-time static recoveries during the rolling process. Rolled tapes with 80 μm in thickness were obtained by applying various deformation sequences between static recoveries to study their effects on the cube texture formation in Ni9.3W alloy substrates. The results show that rising gradient deformation sequence is an advantageous way to obtain a higher amount of cube texture, its content increases by 29.2% compared to that of traditional deformation sequence. The effect of the new recrystallization annealing process on the cube texture formation was analyzed. It is shown that the cube texture content increases with anneal temperature increasing in one-step anneal, but decreases again at higher anneal temperature. Two-step anneal could effectively improve the cube texture content, which could be further enhanced by extending holding time during the first-step anneal. However, too long holding time leads to the decrease in cube texture content. Finally, Ni9.3W alloy substrates with a cube texture content of -90.0 vol% （〈15°） are obtained by optimized two-step anneal.

关键词： Ni9.3W substrates Deformation sequence Anneal process Cube texture

Surface modification of 316L stainless steeldiamond-like carbon films

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Journal of Iron and Steel Research International 2020年第7期27卷 867-874页

作者： Rui-wu Li Zheng Zhang Jian-wei Li Ke-xin ma Yuan-yuan Guo Yan-wen Zhou fa-yu Wu School of materials and Metallurgy University of Science and Technology LiaoningAnshan 114051LiaoningChina Liaoning Censcience Industrial Co. Ltd.Research and Design InstituteLiaoyang 111200LiaoningChina

The diamond-like carbon(DLC)film on 316L stainless steel substrate was preparedpulsed plasma-enhanced chemical vapor deposition,and the performance of the films was optimizedregulating the pulse *** and properties of DLC film on 316L stainless steel were characterizedatomic force microscopy,field-emission scanning electron microscopy,Raman spectra,nano-indenter and electrochemical *** results showed that DLC films with smooth and dense morphology have a low friction coefficient and high nano-indentation hardness,and the surface hardness of 316L stainless steel substrate was enhancedmore than 3 *** mechanical properties of DLC films and their bond with 316L stainless steel could be further optimizedincreasing pulse *** films on 316L stainless steel substrate increased the self-corrosion potential0.173 V and decreased self-corrosion current99%,which significantly improved the anti-corrosive properties of 316L substrate.

关键词： 316L stainless steel Diamond-like carbon film Plasma enhanced chemical vapor deposition Frictional wear Nano-indentation Corrosion resistance

Seismic damage zone and width-throw scaling along the strike-slip faults in the Ordovician carbonates in the Tarim Basin

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Petroleum Science 2019年第4期16卷 752-762页

作者： De-Bo ma Guang-Hui Wu Nicola Scarselli Xin-Sheng Luo Jian-fa Han Zhi-Yong Chen School of Geoscience and Technology Southwest Petroleum UniversityChengdu 610500SichuanChina PetroChina Research Institute of Petroleum Exploration and Development Beijing 100083China fault Dynamics Research Group Department of Earth SciencesRoyal Holloway University of LondonEgham TW20 0EXUK PetroChina Tarim Oilfield Company Korla 841000XinjiangChina

Understanding the scaling relation of damage zone width with displacement of faults is important for predicting subsurface faulting mechanisms and fluid flow processes. The understanding of this scaling relationship is influenced by the accuracy of the methods and types of data utilized to investigate faults. In this study, seismic reflection data are used to investigate the throw and damage zone width of five strike-slip faults a ecting Ordovician carbonates of the Tarim intracraton basin,NW China. The results indicate that fault slips with a throw less than 200 m had formed wide damage zones up to 3000 m in width. Also, damage zone width is found to have both a positive correlation and a power-law relation with throw of two orders of magnitude, with a ratio of these values varying in a range of 2–15. The relationship between throw and damage zone width is not a simple power-law and changes its slope from small to larger size faults. The results indicate that throw scales well with damage zone width for the studied faults, and hence these can be used to predict fault geometries in the Tarim Basin. The study of the wide carbonate damage zones presented here provides new insights into scaling of large-size faults, which involve multiple faulting stages.

关键词： fault damage zone Carbonate Throw Scaling Evolution Tarim Basin

Pd（Ⅱ）-Catalyzed Phosphorylation of Enamido C（sp^2）-H Bonds： A General Route to β-Amido-vinylphosphonates

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Chinese Journal of Chemistry 2018年第9期36卷 809-814页

作者： Baokun qiao Hao-qiang Cao Yin-Jun Huang Yue Zhang Jing Nie fa-Guang Zhang Jun-An ma Department of Chemistry Tianjin Key Laboratory of Molecular Optoelectronic Sciences and Tianjin Collaborative Innovation Center of Chemical Science & Engineering Tianjin University Tianjin 300072 China

Organophosphorus compounds are essential structures in modern pharmaceutical, agrochemical, and material sciences. The development of new and efficient methods for the synthesis of C-P bonds has been an important focus of research. We herein report a Pd-catalyzed enamido C（sp2）-H phosphorylation for direct construction of C-P bonds under simple and convenient conditions without the need for additional ligands or directing groups. The present reaction can tolerate a wide range of functional groups, and furnish a variety of phosphorylation products including tetrasubstituted-vinyl β-aminophosphonates that are otherwise difficult to access. This protocol was also exemplified into the late-stage modification of bioactive natural prod- ucts and was suitable for large-scale synthesis.

关键词： C-H activation phosphorylation palladium catalysis enamines late-stage functionalization

Synergistic effect of RhBMP-2 and bFGF on ectopic osteogenesis in mice

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Asian Pacific Journal of Tropical Medicine 2015年第1期8卷 53-59页

作者： Shu-Yuan ma Zhi-Qiang Feng Ren-fa Lai Zhi-Ying Zhou Zhong-Da Yin First Affiliated Hospital of Ji'nan University

Objective:To investigate the synergistic effect and mechanism of the combined application of recombinant human bone morphogenetic protein-2(rhBMP-2) and basic fibroblast growth factor(bFGF).Methods:24 KM male mice were randomly divided into 6 groups with 4 mice in each group,namely,Group A(control group),Group B(only treated with collagen),Group C(treated with2 ng bFGF+collagen).Group D(treated with 4μg rhBMP-2+collagen),Group E(treated with 4 μg rhBMP-2+2 ng bFGF+collagen) and Group F(treated with 4 μg rhBMP-2+4 ng bFGF+*** composites were implanted into the intermuscular septum of hind legs mice:whereas in control group,intermuscular septum of mice was separated and no implantation was *** observation,detection of concentration of calcium content,micro computed tomography(Micro-CT).three-dimensional reconstruction *** of bone mineral density(BMD).bone volume fraction(BVF) and trabecular thickness(***).as well as histological observation with HE staining and ALP and CD34 immumohistochemical staining were ***:Ectopic osteogenesis was found in Groups D.F and F *** difference in concentration of calcium contents was statistically significant between Groups D and E(P0.05).Micro-CT and three-dimensional reconstruction revealed continuous newborn bone substance in external surface of ectopic bone formation,and the center of bone formation did not show obvious substantial filling by bone *** differences in BMD,BVF and *** were statistically significant between Groups D and E or F(Pmainly located at the edge of ectopic bone formation,and the bone formation in Groups E and F was better than that in Group *** and CD34 immumohistochemical staining revealed the positive expression mainly at the edge of ectopic bone formation,and area of positive expression in Groups E and

关键词： BMP-2 bFCF Ectopic osteogenesis Micro-CT

Increased expression and possible role of chitinase 3-like-1 in a colitis-associated carcinoma model

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World Journal of Gastroenterology 2014年第42期20卷 15736-15744页

作者： Jia-Yi ma Run-Hua Li Kun Huang Gao Tan Chen Li fa-Chao Zhi Guangdong Provincial Key Laboratory of Gastroenterology Department of Gastroenterology Nanfang Hospital Southern Medical University

AIM: To investigate the possible role of chitinase 3-like-1 (CHI3L1) in the progression of colitis-associated carcinoma (CAC).

关键词： Inflammatory bowel disease Ulcerative colitis Colitis-associated carcinoma Murine model Chitinase 3-like-1 Oxidative stress Colorectal cancer

生物转盘耦合垂直流人工湿地对生活污水的净化效果及其微生物群落结构特征

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生态与农村环境学报 2024年第8期40卷 1091-1101页

作者：彭丽萍刘云根杨思林马荣伏川东熊烈钞卢秀秀文明发西南林业大学生态与环境学院云南昆明650224 云南省山地农村生态环境演变与污染治理重点实验室云南昆明650224 云南德源绿创环保科技有限公司云南文山663000

为提高垂直流人工湿地对农村生活污水的净化效率,构建生物转盘耦合垂直流人工湿地系统。以实际生活污水为对象,研究耦合系统对生活污水的净化效果,并采用高通量测序分析其微生物群落结构特征,揭示微生物群落结构与污染物处理效率之间的... 详细信息

为提高垂直流人工湿地对农村生活污水的净化效率,构建生物转盘耦合垂直流人工湿地系统。以实际生活污水为对象,研究耦合系统对生活污水的净化效果,并采用高通量测序分析其微生物群落结构特征,揭示微生物群落结构与污染物处理效率之间的关系。结果表明:系统对化学需氧量(COD)、氨氮(NH_(4)^(+)-N)和总磷(TP)的去除率分别为64.97%、86.84%和79.18%,出水平均质量浓度分别为71.70、3.21和0.67 mg·L^(-1);新型湿地系统适于处理COD、ρ(NH_(4)^(+)-N)和ρ(TP)分别为<250、30~50和<2 mg·L^(-1)的生活污水,且24 h为系统最佳运行时间;2个系统中不同填料区微生物种类无较大差别,相对丰度差别较大,共有的优势菌门、优势菌纲和优势菌目分别有5、8和10类,系统中除氮微生物主要为氢噬胞菌属(Hydrogenophaga)、假单胞菌属(Pseudomonas)等,除磷功能微生物主要有假单胞菌属、脱氯单胞菌(Dechloromonas)、不动杆菌属(Acinetobacter)、红球菌属(Rhodococcus)等;细菌群落影响污染物的去除,NH_(4)^(+)-N、TP和COD去除率与变形菌门和蓝细菌门呈显著正相关,TP浓度与绿弯菌门、COD与绿菌门呈显著正相关(P<0.05);各污染物主要在火山石区、沸石区被去除。研究结果明确了生物转盘耦合垂直流人工湿地微生物群落结构特征及其与污染物去除之间的关系,可为进一步提高人工湿地的处理效率提供科学参考。

关键词：生活污水生物转盘垂直流人工湿地微生物群落结构

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油松人工林土壤微生物对结构调整的响应研究

林业科学研究 2024年第3期37卷 193-202页

作者：法蕾裴顺祥杜满义马淑敏吴莎吴迪王海霞李佳林许基煌中国林业科学研究院华北林业实验中心北京九龙山暖温带森林国家长期科研基地北京102300 中国林业科学研究院热带林业实验中心广西凭祥532600

[目的]为评估结构调整对油松人工林生态系统的影响,探索土壤微生物群落结构动态对结构调整干扰的响应机制。[方法]利用高通量测序技术,对结构调整后山西省中条山油松人工林林下土壤微生物的类群组成及多样性进行探究,分析土壤微生物群... 详细信息

[目的]为评估结构调整对油松人工林生态系统的影响,探索土壤微生物群落结构动态对结构调整干扰的响应机制。[方法]利用高通量测序技术,对结构调整后山西省中条山油松人工林林下土壤微生物的类群组成及多样性进行探究,分析土壤微生物群落的组成结构、多样性及其与环境因素的相互关系。[结果]油松人工林结构调整能够降低土壤的pH值,土壤养分含量显著低于对照样地。土壤微生物的优势菌群未发生较大的变化,土壤的优势细菌类群是变形菌门、放线菌门、酸杆菌门,而优势真菌类群为子囊菌门、担子菌门和被孢菌门。结构调整后油松人工林土壤微生物的丰富度显著增加,多样性较对照样地略有增加,但差异不显著。对结构调整前后的油松人工林微生物类群与土壤理化性质进行RDA分析,pH、总氮、土壤有机质和速效氮是驱动土壤微生物类群变化的主要因子。[结论]结构调整后的油松人工林样地仍处于恢复期,微生物类群结构与未调整样地相比具有相似性,但调整后的土壤微生物类群更为丰富,变形菌门和担子菌门的增加使得土壤中固氮菌的比例提高,土壤微生物类群向有助于有机质分解的方向转换。

关键词：油松人工林结构调整目标树经营土壤微生物微生物群落结构

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