检索结果-南通市图书馆

Structure,defects,and microwave dielectric properties of Al-doped and Al/Nd co-doped Ba_(4)Nd_(9.33)Ti_(18)O_(54)ceramics

引用

Journal of Advanced Ceramics 2022年第4期11卷 629-640页

作者： Weijia GUO Zhiyu MA Yu LUO Yugu CHEN Zhenxing YUE Longtu LI State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China

Low-loss tungsten–bronze microwave dielectric ceramics are dielectric materials with potential application value for miniaturized dielectric filters and antennas in the fifth-generation(5G)communication technology.In this work,a novel Al/Nd co-doping method of Ba_(4)Nd_(9.33)Ti_(18)O_(54)(BNT)ceramics with a chemical formula of Ba_(4)Nd_(9.33+z/3)Ti_(18−z)Al_(z)O_(54)(BNT–AN,0≤z≤2)was proposed to improve the dielectric properties through structural and defect modulation.Together with Al-doped ceramics(Ba_(4)Nd_(9.33)Ti_(18−z)Al_(4z/3)O_(54),BNT–A,0≤z≤2)for comparison,the ceramics were prepared by a solid state method.It is found that Al/Nd co-doping method has a significant effect on improving the dielectric properties compared with Al doping.As the doping amount z increased,the relative dielectric constant(εr)and the temperature coefficient of resonant frequency(τf)of the ceramics decreased,and the Q×f values of the ceramics obviously increased when z≤1.5.Excellent microwave dielectric properties ofεr=72.2,Q×f=16,480 GHz,andτf=+14.3 ppm/℃were achieved in BNT–AN ceramics with z=1.25.Raman spectroscopy and thermally stimulated depolarization current(TSDC)technique were firstly combined to analyze the structures and defects in microwave dielectric ceramics.It is shown that the improvement on Q×f values was originated from the decrease in the strength of the A-site cation vibration and the concentration of oxygen vacancies(VO××),demonstrating the effect and mechanism underlying for structural and defect modulation on the performance improvement of microwave dielectric ceramics.

关键词： microwave dielectric ceramics Ba4Nd9.33Ti18O54(BNT) Al and Al/Nd doping structural and defect modulation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Layer-by-layer self-assembly and clinical application in orthopedics

引用

Journal of materials Science & Technology 2023年第16期147卷 241-268页

作者： Xiao ma Duoyi Zhao Yubo Xiang Yingqi Hua Wei Zhao Yan Cui zhiyu Zhang Department of Orthopedics the Fourth Affiliated Hospital of China Medical UniversityShenyang 110032China Department of Orthopedics Shanghai Bone Tumor InstitutionShanghai General HospitalShanghai Jiao Tong University School of MedicineShanghai 200080China

Orthopedic implants for the treatment of bone defects from various causes have been challenged by insufficient osseointegration,bacterial infection,oxidative stress,immune rejection,and insufficient individualized treatment.These challenges not only impact treatment outcomes but also severely impact patients’daily lives.Layer-by-Layer(LbL)serves as a simple surface coating technique,in simple terms,to functionalize implants by sequentially adsorbing oppositely charged materials onto a substrate.In orthopaedics,LbL self-assembly technology solves some of the challenges by loading various drugs or biological agents on the implant surface and controlling their release precisely to the site of bone defects in a personalized way.This review will introduce the basic principle and the development of LbL in orthopaedics,review and analyze the chemical strategy of LbL in the preparation of bone implants to ensure the stability of the implant,and introduce the use of LbL bone implants in orthopaedics in recent years.The application of LbL includes the realization of programmed drug delivery and sustained release,thereby promoting osseointegration and the formation of new blood vessels,antibacterial,antioxidant,etc.This review focuses on the LbL technology,involving the technology selection for the preparation of bone implants,the chemical strategies of the stability guarantee of LbL implants,the pharmacological properties,loading and release mechanisms of loaded drugs,and the molecular mechanisms of osteogenesis and angiogenesis.The aim of this review is to provide an overview of current research advances,and a prospect in this field was also described.

关键词： Orthopedic implants Layer-by-Layer self-assembly Chemical strategy Agents release Orthopedic applications

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Negative effects of artiffcial nest boxes on birds:A review

引用

Avian Research 2023年第2期14卷 257-266页

作者： Luchang Zhang Xingjian ma zhiyu Chen Chunying Wang Zicheng Liu Xiang Li Xiaoying Xing College of Wildlife and Protected Area Northeast Forestry UniversityHarbin150040China Northeast Asia Biodiversity Research Center Harbin150040China Heilongjiang Luobei Dulu River Wetland Nature Reserve Administration Hegang154200China Heilongjiang Taipinggou National Nature Reserve Administration Hegang154200China Dalian Environmental Monitoring Center Dalian116023China

Artificial nest boxes are placed to attract birds to nest and breed in a specific location,and they are widely used in avian ecology research and in the attraction of insectivorous birds.There is evidence that artificial nest boxes can adversely affect breeding fitness but no great focus has been placed on this issue by researchers.Therefore,we retrieved 321 research papers regarding artificial nest boxes published from 2003 to 2022 and used the'Biblioshiny'program to extract and integrate keywords;we then summarized the adverse effects of artificial nest boxes on avian breeding success.The studies highlighted many drawbacks and misuses in the designing and placement of nest boxes;furthermore,bird attraction was decreased by their inappropriate selection,thus reducing breeding success.Regarding nest box production,there were shortcomings in the construction material,color,smell,and structural design of the boxes used.Nest boxes were also placed at inappropriate densities,locations,orientations,heights,and managed incorrectly.Finally,we propose suggestions for more efficient and safer artificial nest boxes for future use in avian ecology research and bird conservation.

关键词： Artificial nest box Avian breeding management Negative effect Nest box hanging Nest box location Nest box structure

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Construction of Expression Vector for Porcine Gastrin-releasing Peptide Fusion Protein

引用

Agricultural Biotechnology 2022年第3期11卷 72-74页

作者： Zhiyu MA Jie ZHANG Junpei GUO Zhuo ma Chang YU Ying ZHANG Jinlong ZHANG College of Veterinary Medicine Yangzhou University/Jiangsu Co-innovation for the Prevention and Control of Important Animal Infectious Diseases and ZoonosisYangzhou 225009China General Hospital of Eastern Theater Command/Affiliated Jinling Hospital Medical School of Nanjing UniversityNanjing 210002China Institute of Poultry Chinese Academy of Agricultural SciencesYangzhou 225125China

[Objectives]This study was conducted to obtain porcine gastrin-releasing peptide(GRP)fusion protein.[Methods]The constructed pET32a(+)-GRP plasmid was transformed into Escherichia coli BL21(DE3)competent cells to obtain the pET32a(+)-GRP-BL21(DE3)fusion protein expression strain,which was induced with 0.5 mM IPTG at 25℃and 150 r/min for 12 h,and the His-tagged GRP fusion protein was detected by SDS-Page gel electrophoresis and Western Blot.[Results]After optimizing the IPTG-induced expression conditions,it was confirmed that the porcine GRP fusion protein was obtained,and the porcine GRP fusion protein was soluble,stable and highly active.[Conclusions]This study lays a foundation for the subsequent preparation of anti-pig GRP antibodies.

关键词： Gastrin-releasing peptide Vector construction Induced expression Fusion protein Pig

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Effects of LPS on the Gene Expression of NMB and Its Receptor in the Hypothalamic-pituitary-testicular Axis of Rabbits

引用

Agricultural Biotechnology 2020年第6期9卷 33-35,39页

作者： Zhiyu MA Ying ZHANG Junpei GUO Jinlong ZHANG College of Veterinary Medicine Yangzhou University/Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and ZoonosesYangzhou 225009China College of Veterinary Medicine Nanjing Agricultural UniversityNanjing 210095China

[Objectives]This study was conducted to investigate the effect of lipopolysaccharide(LPS)on the gene expression levels of neuromedin B(NMB)and its receptor(NMBR)in the hypothalamic-pituitary-testis(HPT)axis of male rabbits.[Methods]Forty male New Zealand white rabbits were randomly divided into an experimental group injected with LPS and a control group.At 0,1.5,3,6 and 12 h after LPS injection,four rabbits in each group were sacrificed,and the hypothalamus,pituitary and testicular tissues were collected.RT-PCR was carried out to detect the expression of rabbit NMB and NMBR mRNA in the HPT axis.[Results]NMB and NMBR mRNA were expressed in the hypothalamus,pituitary gland and testis of rabbits,and there was a certain time effect,indicating that the NMB/NMBR system is involved in the activities of the hypothalamus-pituitary-testis(HPT)axis.At 1.5 h after LPS stimulation,the expression of NMB mRNA in the hypothalamus increased significantly,and showed an extremely significant difference from the control group(P0.05).The expression levels of NMB and NMBR mRNA in the pituitary and testis tissues in the HPT axis at different time after the LPS treatment were not significantly different from those in the control group(P>0.05).Therefore,LPS stimulation still has a certain effect on the expression of NMB and its receptor mRNA in the HPT axis.[Conclusions]This study is of great significance for the in-depth study on the mechanism of damage caused by immune stress to livestock and poultry reproduction.

关键词： LPS NMB NMBR Hypothalamic-pituitary-testicular axis

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Timing of Displacement along the Yardoi Detachment Fault,Southern Tibet:Insights from Zircon U-Pb and Mica 40Ar-39Ar Geochronology

引用

Journal of Earth Science 2019年第3期30卷 535-548页

作者： Hanwen Dong Yuanku Meng Zhiqin Xu Hui Cao zhiyu Yi Zeliang ma Key Laboratoiy of Deep-Earth Dynamics of Ministry of Natural Resources Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China College of Earth Science and Engineering Shandong University of Science and Technology Qingdao 266590 China School of Earth Sciences and Engineering Nanjing University Nanjing 210023 China

The Yardoi dome is located in the eastern end of the northwest-southeast extending North Himalayan domes (NHD). The dome exposes a granite pluton in the core and three lithologictectonic units separated by the upper detachment fault and the lower detachment fault. The Yardoi detachment fault (YDF), corresponding to the lower detachment fault, is a 800 m strongly deformed top-NW shear zone. LA-1CP-MS zircon U-Pb dating yielded a crystallization ages of 19.57±0.23 to 15.5±0.11 ma for the leucogranite dyke swarm, which indicates that the ductile motion along the YDF began at ca. 20 ma. The 40Ar/39Ar muscovite ages of 14.05±0.2 to 13.2±0.2 ma and the 40Ar/39Ar biotite age of 13.15±0.2 ma, suggest that the exhumation led to cooling through the 370℃ Ar closure temperature in muscovite at ~14 ma to the 335℃ Ar closure temperature in biotite at ~13 ma. Our new geochronological data from the Yardoi dome and other domes in the Tethyan Himalayan Sequences suggest that the ductile deformation in the region began at or before^36 ma in a deep tectonic level, resulting in southward ductile flow at the mid-crustai tectonic level that continued from 20 to 13 ma. Comparing the Yardoi dome to other domes in the NHD, the cooling ages show a clear diachronism and they are progressively younger from the West Himalayan to the East Himalayan.

关键词： leucogranite geochronology Yardoi dome southern Tibet Himalayan Orogen

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Positioning the Southern margin of Asia Prior to Its Collision with India: Paleomagnetic Constraints from Late Cretaceous Dykes in Gangdise Belt

引用

Acta Geologica Sinica(English Edition) 2017年第S1期91卷 50-页

作者： YI zhiyu ma Xuxuan State Key Laboratory for Continental Tectonics and Dynamics Institute of GeologyChinese Academy of Geological SciencesBeijing 100037China

The pre-collisional southern margin of Asia can be restored using paleomagnetic data from late Cretaceous rocks from the Lhasa terrane.However,the available data are based either on the red beds or on the intercalated thin layers of lava flows,both of which had been involved in strongly folding.Recent studies show clear evidence for the possibility of serious overprint hence the data could not be reliably used for tectonic interpretation.We report paleomagnetic data from diorite dykes and the grano-diorite country rock in the Gandise belt near the city of Lhasa.U–Pb isotopic dating indicates the intrusive rocks have an age of;2–86 ma.Fifteen sites yield acceptable Ch RM directions which pass a reversal test.SEM and light microscope observations show primaryintergrowth relationship between magnetite and other minerals within the thin sections.AMS measurement defines a primary magma flow fabric for the intruded dykes and the country rocks.All the characteristics support that the Ch RMs are primary.The paleomagnetic pole calculated from the remanence of the dykes and the country rocks yields a paleolatitude of;4°N which provide a reliable constraint for the southern margin of Asia near Lhasa.Furthermore,the recorded declination shows significant counterclockwise rotation of;0°for the sampling location relative to the north.In consideration of the strike and tectonic setting of the dykes,the strike of the southern margin of Asia is restored which is compatible with the hypothesis of a quasi-linear margin of Eurasia prior to its collision with India.

关键词： Asia Positioning the Southern margin of Asia Prior to Its Collision with India Paleomagnetic Constraints from Late Cretaceous Dykes in Gangdise Belt

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Predicting future dynamics from short-term time series using an Anticipated Learning machine

引用

National Science Review 2020年第6期7卷 1079-1091页

作者： Chuan Chen Rui Li Lin Shu zhiyu He Jining Wang Chengming Zhang Huanfei ma Kazuyuki Aihara Luonan Chen School of Data and Computer Science Sun Yat-sen University Center for Excellence in Molecular Cell Science Shanghai Institute of Biochemistry and Cell Biology Chinese Academy of Sciences School of mathematical Sciences Soochow University Institute of Industrial Science The University of Tokyo International Research Center for Neurointelligence The University of Tokyo Center for Excellence in Animal Evolution and Genetics Chinese Academy of Sciences Key Laboratory of Systems Biology Hangzhou Institute for Advanced Study University of Chinese Academy of Sciences

Predicting time series has significant practical applications over different disciplines. Here, we propose an Anticipated Learning machine(ALM) to achieve precise future-state predictions based on short-term but high-dimensional data. From non-linear dynamical systems theory, we show that ALM can transform recent correlation/spatial information of high-dimensional variables into future dynamical/temporal information of any target variable, thereby overcoming the small-sample problem and achieving multistep-ahead predictions. Since the training samples generated from high-dimensional data also include information of the unknown future values of the target variable, it is called anticipated learning. Extensive experiments on real-world data demonstrate significantly superior performances of ALM over all of the existing 12 methods. In contrast to traditional statistics-based machine learning, ALM is based on non-linear dynamics, thus opening a new way for dynamics-based machine learning.

关键词： dynamics-based machine learning delay embedding theory short-term time series prediction dynamics-based data science

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Formation of disinfection by-products during sodium hypochlorite cleaning of fouled membranes from membrane bioreactors

引用

Frontiers of Environmental Science & Engineering 2021年第5期15卷 271-281页

作者： Hao Wang Defang ma Weiye Shi zhiyu Yang Yun Cai Baoyu Gao Shandong Key Laboratory of Water Pollution Control and Resource Reuse School of Environmental Science and EngineeringShandong UniversityQingdao266237China No.1 Institute of Geology and Mineral Resources of Shandong Province Jinan250014China Shandong Engineering Laboratory for High-Grade Fe Ores Exploration and Exploitation Jinan250014China

Periodic chemical cleaning with sodium hypochlorite(NaClO)is essential to restore the membrane permeability in a membrane bioreactor(MBR).However,the chlorination of membrane foulants results in the formation of disinfection by-products(DBPs),which will cause the deterioration of the MBR effluent and increase the antibiotic resistance in bacteria in the MBR tank.In this study,the formation of 14 DBPs during chemical cleaning offouled MBR membrane modules was investigated.Together with the effects of biofilm extracellular polymeric substances(EPS),influences of reaction time,NaClO dosage,initial pH,and cleaning temperature on the DBP formation were investigated.Haloacetic acids(HAAs)and trichloromethane(TCM),composed over 90%of the DBPs,were increasingly accumulated as the NaClO cleaning time extended.By increasing the chlorine dosage,temperature,and pH,the yield of TCM and dichloroacetic acid(DCAA)was increased by up to a factor of 1–14,whereas the yields of haloacetonitriles(HANs)and haloketones(HKs)were decreased.Either decreasing in the chlorine dosage and cleaning temperature or adjusting the pH of cleaning reagents toward acidic or alkaline could effectively reduce the toxic risks caused by DBPs.After the EPS extraction pretreatment,the formation of DBPs was accelerated in the first 12 h due to the damage of biofilm structure.Confocal laser scanning microscopy(CLSM)images showed that EPS,particularly polysaccharides,were highly resistant to chlorine and might be able to protect the cells exposed to chlorination.

关键词： MBR Biofouling EPS Chemical cleaning DBPs CLSM

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Biosynthesis of Bioadaptive materials:A Review on Developing materials Available for Tissue Adaptation

引用

Journal of materials Science & Technology 2016年第9期32卷 810-814页

作者： Junxuan ma zhiyu Zhou manman Gao Binsheng Yu Deming Xiao Xuenong Zou Cody Bvnger Department of Orthopaedic Peking University Shenzhen HospitalShenzhen 518036China Department of Spinal Surgery/Orthopaedic Research Institute The First Affiliated Hospital of Sun Yat-sen UniversityGuangzhou 510080China Orthopaedic Research Lab/The Institute of Clinical Medicine Aarhus University Hospital8000 Aarhus CDenmark

Biomaterials are increasingly being evolved to actively adapt to the desired microenvironments so as to introduce tissue integration, reconstruct stability, promote regeneration, and avoid immune rejection. The complexity of its mechanisms poses great challenge to current biomimetic synthetic materials. Although still at initial stage, harnessing cells, tissues, or even entire body to synthesize bioadaptive materials is introducing a promising future.

关键词： Biomaterials Bioadaptation Tissue integration Biosynthesis

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：