检索结果-南通市图书馆

Influence of Yb2O3 on the 1.53 μm spectroscopic properties in Er3+/Ce3+ co-doped TeO2-WO3-Na2O-Nb2O5 glasses

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

Optoelectronics Letters 2019年第4期15卷 273-276页

作者： zheng shi-chao KANG Zhong-jian LI Chang-chao ZHOU Ya-xun College of Information and Control Engineering China University of Petroleum Qingdao 266555 China College of Information Science and Engineering Ningbo University Ningbo 315211 China

The Yb2 O3 component was introduced into the Er^3+/Ce^3+ co-doped tellurite glasses with the composition of TeO2-WO3-Na2 O-Nb2 O5 to study the effect of Yb^3+ on the 1.53 μm spectroscopic properties of Er^3+. The X-ray diffraction(XRD) curve and Raman spectrum were measured to investigate the structure nature of synthesized tellurite glasses. The absorption spectrum, upconversion emission spectrum and fluorescence spectrum were measured to evaluate the improved effect of Yb^3+ concentration on the 1.53 μm band fluorescence of Er^3+. Results of the measured 1.53 μm band fluorescence intensity show a significant improvement with the increase of Yb^3+ concentration, while the total quantum efficiency reveals a similar increasing trend. The results of the present work indicate that Er^3+/Ce^3+/Yb^3+ tri-doped tellurite glass has good prospect as a promising gain medium applied for the 1.53 μm broadband amplifier.

关键词： Yb2O3 broadband Yb^3+ X-ray Raman was has

蒲黄的挥发油成分及其体外抗炎、抗氧化活性研究

在线全文

学校读者我要写书评

暂无评论

海峡药学 2024年第2期36卷 31-35页

作者：王自梁郑士超杨晰淼安仁波云南民族大学民族药资源化学国家民委-教育部重点实验室云南昆明650504 延边大学药学院吉林延吉133002

目的分析蒲黄挥发油的化学成分,评价其体外抗炎和抗氧化活性。方法采用乙醚回流提取法结合气流吹扫-微注射器萃取技术(GP-MSE)提取蒲黄挥发油,气相色谱-质谱联用仪(GC-MS)对挥发油成分进行分析并鉴定,归一化法计算各成分的相对含量;MTT... 详细信息

目的分析蒲黄挥发油的化学成分,评价其体外抗炎和抗氧化活性。方法采用乙醚回流提取法结合气流吹扫-微注射器萃取技术(GP-MSE)提取蒲黄挥发油,气相色谱-质谱联用仪(GC-MS)对挥发油成分进行分析并鉴定,归一化法计算各成分的相对含量;MTT法检测蒲黄挥发油对RAW264.7细胞的增殖毒性,通过脂多糖(LPS)诱导RAW 264.7细胞炎症反应,Griess法测定炎症因子一氧化氮(NO)含量,初步评价蒲黄挥发油的体外抗炎作用;通过DPPH自由基清除率和Fe^(3+)还原能力测定评价蒲黄挥发油的体外抗氧化活性。结果从蒲黄挥发油中分离出67个化合物,鉴定其中53个,占挥发油总量的96.89%,其主要化学成分包括:亚油酸、棕榈酸甲酯、棕榈酸、亚油酸甲酯、油酸甲酯、(Z)-9-十四碳烯醛和十八烷酸等;药效评价实验表明,在本实验浓度范围内,蒲黄挥发油能显著抑制LPS诱导的RAW264.7炎症细胞中NO的分泌,对DPPH自由基无明显的清除作用,对Fe^(3+)亦无明显的还原作用。结论蒲黄挥发油的成分以脂肪酸及其简单酯为主,蒲黄挥发油具有一定的体外抗炎活性,但不具有显著的体外抗氧化活性。

关键词：蒲黄挥发油气相色谱-质谱联用抗炎抗氧化

Damage to urban buildings in zones of intensities Ⅷ and Ⅶ during the Wenchuan earthquake and discussion on some typical damages

在线全文

学校读者我要写书评

暂无评论

Earthquake Science 2009年第2期22卷 165-173页

作者： Jingjiang Sun Yuhong Tang chao zheng Hongbin shi Lin Lin Zhongxian Sun Institute of Engineering Mechanics China Earthquake Administration Harbin 150080 China

The outline and typical characteristics of damages to building in Jiangyou city and Anxian county （intensity Ⅷ）, Mianyang city and Deyang city （intensity Ⅶ） are introduced in the paper. The damage ratios, based on the sample statistics of multi-story brick buildings together with multi-story brick buildings with RC frame at first story （BBF）, are presented. Then some typical damages, such as horizontal cricks of brick masonry buildings, X-shaped cricks on the walls under windows, the damages to columns, beams and infill walls of frame buildings and the damage to half circle-shaped masonry walls, are discussed.

关键词： Wenchuan earthquake damage to building seismic intensity

Adverse effect of niobium and boron on hot deformation behavior of sulfur-containing steel

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2024年第1期31卷 252-263页

作者： Guo-ning He shi-qi Wan Bo Jiang chao-lei Zhang Ya-zheng Liu Chun-jing Wu School of Materials Science and Engineering University of Science and Technology BeijingBeijing100083China Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing100083China

The hot deformation behaviors of sulfur-containing gear steel 20MnCr5 containing three different contents of Nb and B(0,0.021%Nb,and 0.024%Nb-0.0022%B)were *** compression and tenssion tests were carried out by Gleeble3800 at the austenite region from 850 to 1150℃and the adverse effects of Nb and B were analyzed by the fracture,microstructure and precipitate *** compression tests showed that the proportions of instable area in hot processing maps of 0.021%Nb and Nb-B steels were higher and the deformability of Nb free steel was *** tensile deformation experiments showed that the reduction areas of Nb free,0.021%Nb and Nb-B steels were 92%-99%,84%-98%and 67%-97%,*** addition of Nb or Nb and B inhibited the dynamic recrystallization during hot deformation,and consequently,more deformed grains were then formed in 0.021%Nb and Nb-B steels thus to obtain the microstructure with worse uniformity and then deteriorate the *** addition,the interaction between inclusions and microalloyed elements was also *** particles of 0.021%Nb and Nb-B steels dynamically precipitated during deformation and precipitated together with MnS thus to worsen the deformability,resulting in the decrease of reduction area.

关键词： Hot deformation Gear steel Processing map Dynamic recrystallization Microalloying

Constructing the Impossible Differential of Type-II GFN with Boolean Function and Its Application to WARP

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

Chinese Journal of Electronics 2024年第1期33卷 80-89页

作者： Jiali shi Guoqiang LIU chao LI College of Liberal Arts and Sciences National University of Defense Technology Hunan Engineering Research Center of Commercial Cryptography Theory and Technology Innovation State Key Laboratory of Information Security Institute of Information Engineering

Type-Ⅱ generalized Feist el network(GFN) has attracted a lot of attention for its simplicity and high *** differential attack is one of the powerful cryptanalytic approaches for word-oriented block ciphers such as Feistel-like *** deduce the impossible differential of Type-Ⅱ GFN by analyzing the Boolean function in the middle *** main idea is to investigate the expression with the variable representing the plaintext(ciphertext) difference words for the internal state *** adopting the miss-in-the-middle approach,we can construct the impossible differential of Type-Ⅱ *** an illustration,we apply this approach to WARP,a lightweight 128-bit block cipher with a 128-bit key which was presented by Banik et *** SAC *** structure of WARP is a 32-branch Type-Ⅱ ***,we find two 21-round truncated impossible differentials and implement a 32-round key recovery attack on *** the 32-round key recovery attack on WARP,some observations are used to mount an effective *** the advantage of the early abort technique,the data,time,and memory complexities are 2125.69chosen plaintexts,2126.6832-round encryptions,and 2100-bit,*** the best of our knowledge,this is the best attack on WARP in the single-key scenario.

关键词： Ciphers Boolean functions Parallel processing Complexity theory

Thiol-Disulfide Exchange Coordinates the Release of Nitric Oxide and Dexamethasone for Synergistic Regulation of Intestinal Microenvironment in Colitis

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Research 2024年第2期6卷 285-300页

作者： Junna Lu Tongfei shi Chengxin shi Fangman Chen chao Yang Xiaochun Xie zheng Wang He Shen Jiaqi Xu Kam W.Leong Dan Shao School of Biomedical Sciences and Engineering South China University of TechnologyGuangzhou International CampusGuangzhouGuangdong 510006China National Engineering Research Center for Tissue Restoration and Reconstruction South China University of TechnologyGuangdong 510006China Department of Plastic and Aesthetic Center The First Affliated Hospital of Zhejiang UniversityHangzhou 310000China Department of Biomedical Engineering Columbia UniversityNew YorkNY 10027USA School of Medicine South China University of TechnologyGuangzhouGuangdong 510006China CAS Key Laboratory of Nano-Bio Interface Suzhou Institute of Nano-Tech and NanoBionicsChinese Academy of SciencesSuzhou 215123China CAS Key Laboratory for Biomedical Efects of Nanomaterials&Nanosafety CAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijing 100190China Guangdong Provincial Key Laboratory of Biomedical Engineering South China University of TechnologyGuangzhou 510006China Key Laboratory of Biomedical Materials and Engineering of the Ministry of Education South China University of TechnologyGuangzhou 510006China

The cell-specific functions of nitric oxide(NO)in the intestinal microenvironment orchestrate its therapeutic effects in ulcerative *** most biomaterials show promise by eliciting the characteristics of NO,the insufficient storage,burst release,and pro-inflammatory side effects of NO remain as ***,we report the development of thiol-disulfide hybrid mesoporous organosilica nanoparticles(MONs)that improve the storage and sustained release of NO,broadening the therapeutic window of NO-based therapy against *** tailored NO-storing nanomaterials coordinated the release of NO and the immunoregulator dexamethasone(Dex)in the intestinal microenvironment,specifically integrating the alleviation of oxidative stress in enterocytes and the reversal of NO-exacerbated macrophage ***,such a synchronous operation was achieved by a self-motivated process wherein the thiyl radicals produced by NO release cleaved the disulfide bonds to degrade the matrix and release Dex via thiol-disulfide ***,the MON-mediated combination of NO and Dex greatly ameliorated intractable colitis compared with 5-aminosalicylic acid,even after delayed ***,our results reveal a key contribution of synergistic modulation of the intestinal microenvironment in NO-based colitis therapy and introduce thiol-disulfide hybrid nanotherapeutics for the management of inflammatory diseases and cancer.

关键词： sustained release disulfide

Experimental and numerical simulation study on the erosion behavior of the elbow of gathering pipeline in shale gas field

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

Petroleum Science 2024年第2期21卷 1257-1274页

作者： En-Bin Liu Shen Huang Ding-chao Tian Lai-Min shi Shan-Bi Peng He zheng Petroleum Engineering School Southwest Petroleum UniversityChengdu 610500SichuanChina Chongqing Natural Gas Sales Center Natural Gas BranchSinopecChongqing400023China Zhejiang Zheneng Natural Gas Operation Co. Ltd.Hangzhou 310000ZhejiangChina School of Civil Engineering and Architecture Southwest Petroleum UniversityChengdu 610500SichuanChina Louisiana Tech Univ Trenchless Technol Ctr599 Dan Reneau DrRustonLA71270USA Southwest Oil and Gas Field Branch Natural Gas Research Institute Chengdu 610213SichuanChina

During the production period of shale gas, proppant particles and rock debris are produced together,which will seriously erode the elbows of gathering pipelines. In response to this problem, this paper takes the elbow of the gathering pipeline in the Changning Shale Gas Field as an example to test the erosion rate and material removal mechanism of the test piece at different angles of the elbow through experiments and compares the four erosion models with the experimental results. Through analysis, it is found that the best prediction model for quartz sand-carbon steel erosion is the Oka model. Based on the Oka model, FLUENT software was used to simulate and analyze the law of erosion of the elbow of the gas gathering pipeline under different gas flow velocities, gas gathering pressure, particle size, length of L1,and bending directions of the elbow. And a spiral pipeline structure is proposed to reduce the erosion rate of the elbow under the same working conditions. The results show that this structure can reduce erosion by 34%.

关键词： Shale gas Gas gathering pipeline Elbow Erosion CFD

Interface structure of α-Mg/14H-LPSO:First-principles prediction and experimental study

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2024年第9期42卷 1792-1799,I0006页

作者： Yuan shi Xiaohua Zhang Hongyan Yue chao Li School of Materials Science and Chemical Engineering Harbin University of Science and TechnologyHarbin150040China

The interfacial structure of the α-Mg/14H-LPSO phase in rare earth-including magnesium alloy was investigated via high-angle annular dark-field scanning transmission electron microscopy(HAADFSTEM) imaging and first-principles calculations of density-functional *** possible interfacial models were constructed according to the different terminations of the LPSO phase,and the corresponding interfacial energies were calculated,from which the four most stable structures(Terl-MgY-hollow,Ter2-Zn-hollow,Ter3-MgYII-hollow and Ter4-Mg-bridge) were *** interfacial phase diagrams related to the Y chemical potentials were obtained from the calculations,and the most stable interfacial structure was ***-MgY-hollow and Ter2-Zn-hollow have the lowest interfacial energies in the range of-0.7 eV <Δμγ<-0.6 eV,where fluctuating change of state is the minimized and the interface is the most *** separation work of the two models was calculated to predict the bonding strength of the structures at both ends of the *** calculation results show that the maximum interfacial separation work is 1.45 J/m~2 for the interface model of α-Mg and 14H-LPSO phase structure with Ter2-Zn-hollow termination.

关键词： Rare earths Magnesium alloy HAADF-STEM LPSO First-principles Interface

Diffractive neural networks with improved expressive power for gray-scale image classification

在线全文

学校读者我要写书评

暂无评论

Photonics Research 2024年第6期12卷 1159-1166页

作者： MINJIA zheng WENZHE LIU LEI shi JIAN ZI State Key Laboratory of Surface Physics Key Laboratory of Micro-and Nano-Photonic Structures(Ministry of Education)and Department of PhysicsFudan UniversityShanghai 200433China Institute for Nanoelectronic Devices and Quantum Computing Fudan UniversityShanghai 200433China Collaborative Innovation Center of Advanced Microstructures Nanjing UniversityNanjing 210093China Shanghai Research Center for Quantum Sciences Shanghai 210315China

In order to harness diffractive neural networks(DNNs)for tasks that better align with real-world computer vision requirements,the incorporation of gray scale is ***,DNNs are not powerful enough to accomplish gray-scale image processing tasks due to limitations in their expressive *** our work,we elucidate the relationship between the improvement in the expressive power of DNNs and the increase in the number of phase modulation layers,as well as the optimization of the Fresnel number,which can describe the diffraction *** demonstrate this point,we numerically trained a double-layer DNN,addressing the prerequisites for intensitybased gray-scale image ***,we experimentally constructed this double-layer DNN based on digital micromirror devices and spatial light modulators,achieving eight-level intensity-based gray-scale image classification for the MNIST and Fashion-MNIST data *** optical system achieved the maximum accuracies of 95.10%and 80.61%,respectively.

关键词： process mirror limitations